Colloquial Welsh prepositions


Colloquial Welsh prepositions deals with the prepositions of the colloquial Welsh language, the spoken register of the modern Welsh language as spoken in Wales by first-language speakers. This page does not deal with the literary standard forms of the prepositions nor any dialect which may have arisen outside of Wales. Welsh has two standardised forms: Literary Welsh – a conservative language reserved for literary purposes which retains some features of older Welsh; and Colloquial Welsh – the Welsh one will hear being spoken in Welsh speaking areas. For the most part the two languages share prepositions, though for some of them their usages can differ; there are also some which have lost their inflected forms in the colloquial language but is preserved in the literary standard. Colloquial Welsh also shows some variation in initial-consonant mutations, which is explained below, while the literary form retains the "proper" mutations in all cases. Welsh prepositions do perform the same roles as English prepositions but there is variation and these must be learnt as they are encountered. For instance it is often taught that Welsh am means 'for' and i means 'to'; this is not incorrect but am can also mean 'about' or 'at' and i can mean 'for'. The usages given below outline how each preposition is used in modern colloquial Welsh.

Definitions of Welsh prepositions

Prepositions are words like on, at, to, from, by and for in English. They often describe a relationship, spatial or temporal, between persons and objects. For example, 'the book is on the table'; 'the table is by the window'.
Welsh prepositions come in two categories: simple prepositions and compound prepositions ; the former are single words, like English on, at, from, to etc. while the latter consist of a simple preposition + some other element like English in front of or in addition to. Compound prepositions are less frequent than simple prepositions and are discussed below.

Simple prepositions

There are approximately two dozen or so simple prepositions in modern colloquial Welsh. While some have clear-cut and obvious translations, others correspond to different English prepositions depending on context. As with all areas of modern Welsh, some words are preferred in the North and others in the South.
The main prepositions used in modern colloquial Welsh are :
Most of these share the following characteristics:
  1. they cause mutation of the following word
  2. they inflect for person and number, similar to verbs
  3. they can be used with a following verbal-noun

    Mutations after prepositions

The majority of Welsh prepositions cause mutation to the following word – the most common, by far, is the soft mutation. Examples:
Several do not cause any mutation, while â, gyda and tua should cause aspirate mutation but in reality they are usually left unmutated, since the aspirate mutation is dying out and for many speakers only mutation of c- /k/ is normal while mutation of p- /p/ and t- /t/ is not. Yn ‘in’ alone causes the nasal mutation which also is not as widespread as suggested by the literary standard and is often replaced by the soft mutation. Personal names are not mutated after prepositions but names of places and other nouns are: i ferch ‘to a girl’, o Fangor ‘from Bangor’, but i Dafydd ‘to italic=no’, not *i Ddafydd.

Inflected prepositions

When used with a personal pronoun, most prepositions insert a linking syllable before the pronoun. This syllable changes for each preposition and results in an inflection pattern similar to that found in Welsh verbs. Broadly speaking, the endings for inflected prepositions are as follows:
There is some dialect variation between these endings, particularly with 1st and 2nd pers. sing., which can often end in -o i and -ot ti and 2nd pers. pl. -och chi is often heard as -ach chi. 3rd pers. sing. and 3rd pers. pl. endings are always as shown but almost always omit the pronoun element, leaving the inflectional ending by itself to indicate person:
But note that the 3rd pers. pl. -yn nhw is never shortened in this manner.
These differ from the literary standard where the 1st pers. sing. is -af i; the 1st pers. pl. is -om ni; the 3rd pers. sing. masc. is -o ef and the 3rd. pers. pl. is -ynt hwy. The literary standard also has the alternative 2nd pers. pl. pronoun chwi. Most of these are never encountered in the colloquial language and therefore will not be presented in the inflected forms in this article.
The linking element between the preposition and the ending is more complicated, however. Different prepositions use a different linking element. For example, am inserts -dan- before its endings, while heb uses -dd- Rhwng changes its vowel as well as inserting -dd- while some, like at and wrth add the endings with no linking element and some, like gyda and efo do not inflect at all.

Prepositions and their uses

 causes aspirate mutation. It means ‘with’, but note that there are other equivalents to ‘with’ in Welsh Use of â/ag is fairly restricted:
  1. It indicates the means by which something is done or achieved, or the instrument of an action:
  2. # Nes i agor ‘y mys i â chyllell fara – ‘I cut my finger with a breadknife’
This usage often uses ‘by’ in English as an alternative to ‘with’:
  1. #
  2. Gawn ni dalu â siec fan hyn? – ‘Can we pay by cheque here?’
  4. Where the relationship between two objects is regarded as a close and permanent association, â/ag is more common than gyda or efo.
  5. It means ‘as’ with equative forms of adjectives:
  6. # Mor ddu â’r fran – ‘As black as the crow’’
  7. Used idiomatically with the verbs mynd and dod to create mynd â ‘take’ and dod â ‘bring’ . The Welsh word cymryd 'take' strictly means 'take hold of, seize, grab' and cannot be used in place of mynd â.
  8. Â/ag is used with many common verbs like siarad 'speak', cwrdd 'meet' and ymweld 'visit' to make siarad â, cwrdd â and ymweld â in which case Welsh aligns more with American English than with British English:
  9. # Dim ond ddoe o'n i'n siarad ag e – 'It was only yesterday I was speaking to him'
  10. # Lle gwrddest ti â fe gynta? – 'Where did you first meet him?'

  1. # Pa mor aml dach chi'n ymweld â'ch nain yn y Gogledd? – 'How often do you visit your grandmother up North?'
  2. The verb peidio 'stop, cease' is used to form negative commands and is followed by â/ag in the standard language but its use is entirely optional in speech with the exception of certain set phrases, e.g. paid â malu 'stop talking nonsense'. In the colloquial language both paid â phoeni and paid poeni are commonly heard.

Am is a very common preposition in spoken Welsh with a range of English equivalents:
  1. 'Exchange for' – this meaning is used with verbs like talu 'pay' to give talu am 'pay for' :
  2. # Dales i bedair punt am y rhain – 'I paid four pounds for these'
  3. In time expressions Welsh am is equivalent to English 'at':
  4. #Ddo i'n ôl am saith – 'I'll come back at seven'

  1. Am means 'for' in expressions of duration of time:
  2. # Fuon nhw yng Ngogledd yr Eidal am fis – 'They were in Northern Italy for a month'
  3. Am means 'about/concerning' when used with the verbs siarad 'speak/talk', sôn 'speak/talk' and meddwl 'think':
  4. # Am beth dych chi'n siarad? – 'What are you talking about?'
  5. # Gawn ni weld be' mae'n feddwl am hynny – 'We will see what s/he thinks about that'
  6. Spatially, am means 'about/around' with a sense of something actually being surrounded or enclosed:
  7. # Rhowch rwymyn am ei ben o – 'Put a bandage around his head'
Phrases like 'around the town' require a compound preposition like o amgylch or o gwmpas.
  1. When am precedes a verbal-noun it means '... want to...':
  2. # Wyt ti am ddod 'da ni neu beidio? – 'Do you want to come with us or not?'
  3. # Dw i am siarad ag e cyn iddo fynd – 'I want to talk to him before he goes'
Using am to mean 'about' with verbs has been discussed above. With most other verbs am usually means 'for':
Am also has other meanings in the literary language which are not a feature of colloquial Welsh, such as 'towards'.
Inflected forms of am
The table below gives the inflected forms of am with their accompanying pronouns:

Ar has a number of English equivalents, but usually equates to 'on'.
  1. Ar means 'on' in a purely spatial sense with location and motion:
  2. # Mae'r llyfr ar y bwrdd – 'The book is on the table'
  3. # Rho'r llyfr ar y bwrdd – 'Put the book on the table'
  4. It means 'about to' when followed by a verbal-noun:
  5. # Brysiwch, mae'r trên ar fynd! – 'Hurry up, the train's about to go!'
  6. # Mae teledu lloeren ar ddod – 'Satellite TV is almost here'
  7. # Pan o'n i ar wneud hynny – 'When I was about to do that'
  8. Ar is used with expressions of temporary physical and mental states, like illnesses. It often corresponds to English 'have':
  9. # Mae'r ddannodd arna i – 'I've got toothache
  10. # Roedd y ffliw arni – 'She had flu'
  11. # Mae Coronafeirws ar Angharad – 'Angharad has Coronavirus'
  12. # Oes ofn arnat ti? – 'Are you afraid?'
  13. Ar can mean 'of' when talking about a part or sample:
  14. # Dim ond rhyw flas ges i arno fo – 'I only got a taste of it'
  15. # Blas ar Gymru – 'a taste of Wales'
  16. Ar is often used with expressions of time and the weather where its English equivalent can change:
  17. # ar Ddydd Llun – 'on a Monday, on Mondays'
  18. # ar yr un adeg – 'at the same time'
  19. # ar dywydd poeth – 'in hot weather'
  20. Ar is used with the verbs gwrando 'listen' and edrych 'look' to make gwrando ar 'listen to' and edrych ar 'watch'. A common mistake made by learners is to use the preposition i :
  21. # Ar beth dach chi'n gwrando? – 'What are you listening to?'
  22. # Ar beth wyt ti'n edrych? – 'What are you watching?'
  23. # Dw i'n edrych ar y teledu – 'I'm watching TV'
  24. # Mae o'n gwrando ar Pink Floyd – 'He's listening to Pink Floyd'
Inflected forms of ar
The table below gives the inflected forms of ar with their accompanying pronouns:

While Welsh at often corresponds to English 'at', the field of scope of Welsh at is far wider.
  1. At is used for English 'to' when it implies motion up to a destination. In Welsh we must say, for example, danfon llythyr at Sioned 'send a letter to Sioned' but danfon llythyr i Lundain 'send a letter to London' – Sioned is a person and takes at, London is a place and takes i. More examples:
  2. # Rhaid ini fynd â ti at y deintydd bore fory – 'We must take you to the dentist tomorrow morning'
  3. # Lluchiwch y bêl ata i! – 'Chuck the ball to me!'
  4. It can mean 'for' with the sense of 'benefit/good/purpose of':
  5. # At beth mae hwnna i fod? – 'What's that supposed to be for?
  6. # Mae'r arian i gyd yn mynd at achosion da – 'All the money is going to good causes'
  7. Tuag at is the usual expression corresponding to the literary term tua 'towards'. In the colloquial language tua now means 'about' in expressions of time.
  8. # Rhedwch chi i gyd tuag ata i! – 'All of you run towards me!'
  9. Hyd at is a variant of hyd 'up to':
  10. # Dyma hi wedyn yn cochi hyd at ei chlustiau – 'Then she blushed right up to her ears'
Some verbs which use at include:
Inflected forms of at
The table below gives the inflected forms of at with their accompanying pronouns:

Cyn means 'before' in expressions of time, never in spatial expressions, e.g. cyn y Rhyfel 'before the War' or cyn deg o'r gloch 'before 10 o'clock'. It is also used as a conjunction. Cyn does not cause a mutation, nor does it have inflected forms. Examples of cyn:
It is important for anyone learning Welsh to understand that the compound preposition o flaen 'in front of' cannot be used instead of cyn. The two are not interchangeable despite their interchangeability in English in sentences like 'to stand before/in front of the building':
As an adjectival prefix, cyn- always means 'ex-' or 'former'.

Dan causes soft mutation and means 'under': dan y dŵr 'under the water', dan ddylanwad ei reini 'under the influence of his parents'. The related compound preposition oddidan means 'from under'.
The term dan ofal 'under care', abbreviated to d/o is the norm for 'care of' when addressing letters.
The two most important idioms using dan are:
  1. Dan ei sang – 'full to bursting, packed'
  2. Dan haul – 'under sun'
The unmutated form, tan is now, to all intents and purposes, obsolete in this meaning and has become a separate preposition in its own right and means 'until / till'.
Inflected forms of dan
The table below gives the inflected forms of dan with their accompanying pronouns:

Dros

Dros has two variants: tros and drost. Dros causes soft mutation and means:
  1. 'Over' in a purely spatial sense. For example, dros y bont 'over the bridge', edrych dros y clawdd 'look over the hedge'. It can also mean 'all over' when speaking about a large area: Mae caneuon Meinir Gwilym yn boblogaidd dros Gymru gyfan 'Meinir Gwilym's songs are popular all over Wales'.
  2. 'Over' in the sense of 'more than' : Mae dros fil o bobol yn y neuadd yn barod 'There are over a thousand people in the hall already'.
  3. 'For' in the sense of 'on behalf of':
  4. # Nei di fynd lawr i'r siop drosta i? – 'Will you go to the shop for me?'
  5. # Dan ni i gyd yn teimlo drostat ti – 'We all feel for you
  6. When used with nouns like rheswm 'reason' and esgus 'excuse' equates to English 'for':
  7. # Alla i'm gweld unrhyw reswm dros ymddwyn fel 'ny – 'I can see no reason for behaving like this'
  8. # Barn Huw ydy fod 'na ddim esgus dros ragrith – 'Huw is of the opinion that there is no excuse for hypocrisy'
Idioms using dros tend to be adverbial. Two very common and useful set phrases using dros are:
  1. Dros ben llestri – 'Over the top'
  2. # Sdim eisiau mynd dros ben llestri, nag oes? – 'There's no need to go over the top, is there?'
  3. Dros ben – 'Exceedingly'
  4. # Mae'r sefyllfa yn un ddifrifiol dros ben – 'The situation is exceedingly serious '
Inflected forms of dros'
The table below gives the inflected forms of dros'' with their accompanying pronouns:

Efo

Efo does not cause mutation and is a general word meaning 'with' and is restricted to Northern dialects of the spoken language. In the South #Gyda / gydag is always used instead. The only appearance of gyda in the North is in set phrases like gyda'r nos 'in the evening'. Efo and gyda are not, however, always interchangeable as gyda is used in the South to express possession; in the North this is not achieved by efo but by gan. The following examples are all Northern dialect where efo can be substituted for gyda in the South:
  1. Dan ni'n mynd i'r Swisdir efo'r Jonesiaid eleni – 'We are going to Switzerland with the Jonses this year'
  2. Hefo pwy dach chi'n rhannu tro 'ma, 'ta? – 'Who are you sharing with this time, then?'
  3. Mi ddo i hefo chdi rŵan – 'I'll come with you now'
Efo does not have inflected forms.

Gan

Gan causes soft mutation. It is another Northern dialect word used to express possession and is replaced by #Gyda / gydag in the South. Mae gan Mrs Williams gath fawr 'Mrs Williams has a large cat'. Although gan and gyda are interchangeable in this context, the structure of the sentences differs and it is not as simple as substituting one word for the other. The following example sentence is translated using gan and gyda and means 'do you have enough money?':
  1. Oes gen ti ddigon o arian?
  2. Oes digon o arian gyda ti?
There are, however, other uses for gan not involving possession and are therefore common in both the North and the South:
  1. 'by' in passive sentences
  2. # Fe geith copïau o'r llyfr eu harwyddo gan yr awdur bore fory – 'Copies of the book will be signed by the author tomorrow morning'
  3. # Ges i mrathu gan gi ar y ffordd adre – 'I got bitten by a dog on the way home'
  4. By extension of 1 it is also used to mean 'by' as in the author of a work:
  5. # The Lord of the Rings gan J. R. R. Tolkien
  6. Equates to English 'from' or 'off' where something is handed over or transmitted from one thing to another:
  7. # Ges i bunt gynno fo – 'I got a pound off him'
  8. # Pa newyddion gaethon nhw gynni hi? – 'What news did they get from her?'
  9. # Gyn bwy gest ti fenthyg ono fo? – 'Who did you borrow it from?'
  10. When used with verbal-nouns gan can imply a simultaneous action:
  11. # Aethon nhw lawr y stryd gan guro ar y drysiau i gyd – 'They went down the street banging on all the doors'
  12. # Gan feddwl, dw i ddim yn siwr fyddai hynny'n syniad da – 'Thinking about it, I'm not sure that would be a good idea'
In this sense the pronunciation is usually gan and not gyn.
Some common idioms using gan:
  1. Mae'n ddrwg gen i – 'I'm sorry'
  2. well gen i – 'I prefer'
  3. Mae'n dda gen i gwrdd â chi – 'I'm pleased to meet you'
Inflected forms of gan
The table below gives the inflected forms of gan with their accompanying pronouns:

Ger does not cause a mutation and is used with geographical locations to mean 'in the vicinity of':
  1. Ger Barcelona mae Mark a'i deulu'n byw bellach – 'Mark and his family live near Barcelona now'
  2. Dan ni'n byw mewn pentre bach ger Harlech – 'We live in a small village near Harlech'
Ger is related to the term gerbron which means 'before' in the sense of 'in the presence of' or 'for the attention of' and is used with nouns like llys 'court' or bwrdd 'board':
  1. Daethpwyd â chwe achos gerbron y llys bore 'ma – 'Six cases were brought before the court this morning'
  2. Bydd y bwrdd yn rhoi ystyriaeth fanwl i'r holl dystiolaeth a roddwyd gerbron yr wythnos hon – 'The board will carefully consider all the evidence that has been presented this week'
Ger has no inflected forms.

Gyda causes aspirate mutation and is the general term for 'with' in the South. With the exception of idioms, it is usually heard as 'da in speech: Oes amser 'da chi i brynu'r tocynnau? 'Have you got time to buy the tickets?'
Gyda/gydag is used in the South to show possession, as gan is used in the North, but their forms differ, compare the following sentence – 'do you have enough food?':
  1. Oes digon o fwyd 'da ti?
  2. Oes gen ti ddigon o fwyd?
Gyda/gydag does not have inflected forms, so gyda fi, gyda ti, gyda nhw but note that 'with him' can be either da fe or dag e.

Heb

Heb causes soft mutation and in its primary meaning, heb means 'without': heb arian 'without money', peidiwch mynd hebdda i! 'don't go without me!'.
Heb can be used with a verbal-noun to make a negative construction in the perfect tense – equivalent to ddim wedi: Dan ni heb benderfynu 'We haven't decided' ; Mae o heb fynd eto 'He hasn't gone yet'.
Heb + possessive adjective + verbal-noun corresponds to 'which/who has/have not been' or an adjectival 'un....ed': pobol heb eu cofrestru 'people who have not been registered / unregistered people' ; pryd o fwyd heb ei fwyta 'an uneaten meal' .
Some idioms using heb:
  1. Heb ei ail – 'second-to-none, first-rate'
  2. # Dyma bortread heb ei ail o fywyd y glowyr yn y tridegau – 'This is a first-rate portrayal of miners' lives in the thirties'
  3. Yn amlach na heb or yn fyw na heb – 'more often than not'
  4. # Yn amlach na heb, mae'r fath ymddygiad yn arwain at drychineb – 'More often than not, this kind of behaviour leads to disaster'
Inflected forms of heb
The table below gives the inflected forms of heb with their accompanying pronouns:

Hyd causes soft mutation and has the following meanings:
  1. 'up to, until' in a temporal sense. In this sense it is often interchangeable with tan.
  2. # Mae'r cyrsiau'n para hyd ddiwedd mis Mehefin – 'The courses go on until the end of June'
  3. 'up to' in a spatial sense and is often expanded to hyd at:
  4. # Oedd e hyd at ei wddw yn y dŵr – 'He was up to his neck in the water'
  5. # Wedson nhw 'tha i am dalu hyd at ugain punt a dim mwy – 'I was told to pay up to twenty pounds and no more'
Pronouns are not normally used with this preposition.
The following are all commonly used idioms using hyd, though it is not strictly a preposition in all cases:
  1. Cael hyd i – 'find'
  2. # Gest ti hyd iddo? – 'Did you find it?'
  3. Dod o hyd i – 'find'
  4. # Daethpwyd o hyd i gorff – 'A body has been found'
  5. Hyd yn oed – 'even'
  6. # Mae hyd yn oed Gareth wedi dod – 'Even Gareth has come'
  7. Hyd yn hyn – 'so far, up till now'
  8. # 'Sdim sôn am fynd at y llysoedd hyd yn hyn – 'There's no talk of going to the courts so far'
  9. O hyd – 'still; all the time'
  10. # Dyn ni yma o hyd – 'We're still here'
  11. # Mae o'n siarad o hyd am ei ffôn symudol – 'He's always going on about his mobile phone'
  12. Hyd y gwela i – 'as far as I can see'
  13. # Fydd 'na ddim problemau hyd y gwela i – 'There'll be no problems as far as I can see'
  14. hyd y gwn i – 'as far as I know'
  15. # Mae popeth wedi'i drefnu, hyd y gwn i – 'Everything's set, as far as I know'
  16. Hyd also appears as a conjunction meaning 'until' with a following verb
  17. # Ewch ymlaen ffordd 'ma hyd gwelwch chi faes chwarae ar y dde – 'Go on this way until you see you see a playing field on the right'
  18. The compound preposition ar hyd 'along, the length of...' and with units of time 'all....... long'
  19. # Ewch ar hyd y ffordd 'ma am ddeng munud, yna trowch i'r dde – 'Go along this road for ten minutes, then turn right'
  20. # Ar hyd y nos – 'All night long'
Hyd does not have inflected forms.

I causes soft mutation and often, but by no means always, corresponds to English 'to'. It is possibly the most frequently used preposition in the spoken Welsh language.
I corresponds to English 'to' in the following senses:
  1. Motion towards or into a place
  2. # Dych chi'n mynd i'r dre heddiw? – 'Are you going to town today?'
  3. Used with the indirect object. Note that English can omit this preposition but Welsh always requires i.
  4. # Roddes i'r llyfr i Fred – 'I gave the book to Fred'
  5. # Elli di ddangos hwnna i mi am eilliad? – 'Can you show me that a moment?'
  6. Equates to English 'to' with the sense of 'purpose' or 'in order to' when followed by a verbal-noun:
  7. # Fe adawodd y ddwy onyn nhw'n gynnar i ddal y bws – 'They both left early to catch the bus'
  8. # Ddaethon ni â'r pris lawr i ddenu mwy o bobol – 'We brought the price down to attract more people'
In this sense the compound preposition er mwyn 'in order to' is often used as an alternative:... er mwyn dal y bws... and...er mwyn denu mwy o bobol, etc.
Other common uses for i which do not correspond to 'to':
  1. English 'for'
  2. # Mae gen i lythyron i chi – 'I've got some letters for you'
  3. # Nes i'r holl waith paratoi i ti bore 'ma – 'I did all the preparation for you this morning'
  4. # Arhoswch funud - na i llnau nhw i chi – 'Wait a minute - I'll clean them for you'
  5. I can denote possession – especially when gyda/gan is not possible due to the nature of the sentence:
  6. # Mae'r bobol 'na'n ffrindiau i mi – 'Those people are friends of mine'
  7. Used after verbs of making or causing:
  8. # Paid gwneud i Eleri chwerthin wrth iddi fwyta – 'Don't make Eleri laugh while she is eating'
  9. # Yr unig esboniad a roddwyd oedd mai taro rhewfryn a achosodd iddi suddo – 'The only explanation given was that it was hitting an iceberg that caused her to sink'
  10. Used after conjunctions to introduce the subject:
  11. #...cyn i mi fynd – '...before I go'
  12. #...er mwyn iddo ddeall – 'so that he can/could understand'
  13. Means 'that' in past tense sentences + subject + verbal-noun:
  14. # Dw i'n eitha siwr iddi ffonio rywbryd ddoe – 'I'm pretty sure she phoned some time yesterday'
When i follows a verb its meaning usually parallels English but the English preposition can often be omitted. The word gofyn 'to ask' must also take i which may be unexpected by English speakers.
  1. Gofynnwch iddo fo ydy o'n dod – 'Ask him if he is coming'
  2. Efallai y byddwch chi eisiau gofyn i'r plant am eu syniadau nhw – 'Perhaps you will want to ask the children for their ideas'
The idiom rhoi gwybod i means 'inform' or 'let..... know':
  1. Rhowch wybod i mi os glywch chi rywbeth – 'Let me know if you hear anything'
The idiom yn dal i is used to mean 'still....ing':
  1. Mae Seren yn dal i deimlo'n sâl – 'Seren is still feeling ill'
  2. Mae'n dal i fwrw – 'It's still raining'
Even though i can cover 'into' to the house'; i Gymru ' the expanded form i mewn i can be used where this is the central idea or where it is emphasised:
  1. Drychon ni o amgylch yr ardd, wedyn mynd i mewn i'r tŷ ei hun – 'We had a look around the garden, then we went into the house itself'
Inflected forms of i
The table below gives the inflected forms of i with their accompanying pronouns:
Notes:
  1. i mi and i fi are interchangeable but i fi is much more common in the South.
  2. An older form of the 2nd pers. pl. iwch is still heard in the expression Nos dawch!, 'sdawch! 'Good night!' and is heard in the North.

Mewn does not cause mutation and should not be confused with i mewn. It means 'in' but is only used where the following noun is non-specific. Specific nouns require the use of yn. Compare:
  1. mewn tŷ – 'in a house'; but yn y tŷ – 'in the house'
  2. mewn ardaloedd gwledig – 'in rural areas'; but yn yr ardaloedd gwledig – 'in the rural areas'
  3. mewn gwladwriaeth ddemocrataidd – 'in a democratic state'; but yn Israel – 'in Israel'
  4. mewn gwlad estron – 'in a foreign country'; but yn Lloegr – 'in England'
Mewn does not have inflected forms.

O causes soft mutation. It equates to English 'from' and 'of', but care must be taken – o cannot be used for genitive constructions for which Welsh has a specific method of constructing. Care should also be taken not to confuse the preposition with the pronoun o. O has the following meanings:
  1. 'From' in most English senses, whether motion is implied or not.
  2. # Dw i'n dod o Fangor yn wreiddiol – 'I come from Bangor originally'
  3. # O Lanfairpwll ar Ynys Môn mae'r gantores Elin Fflur yn dod – 'The singer Elin Fflur comes from Llanfairpwll on Anglesey'
  4. # Mae mrawd i'n llogi tŷ yn Nyfnaint o fis Mehefin tan fis Medi – 'My brother's renting a house in Devon f.rom June to September'
  5. 'Of' in quantity expressions or where part of something is implied
  6. # Wi'n moyn hanner pwys o gaws a dwy botel o laeth – 'I want half a pound of cheese and two bottles of milk'
  7. O can also be used with verbal-nouns:
  8. # O ystyreid mai dyma'r tro cynta iddo siarad yn gyhoeddus, mae'n edrych yn hyderus iawn – 'Considering that this is the first time he's spoken in public, he looks very confident'
  9. # O'n i'n mynd i fod yn grac, ond o siarad â nhw mae'n amlwg fod 'na ryw gamddealltwriaeth wedi bod yn rhywle – 'I was going to be cross, but speaking to them it's clear that there's been some misunderstanding somewhere'
  10. O can convey adverbial '-ly' where it qualifies and adjective – arbennig o dda 'especially good', hynod o galed 'extraordinarily hard'
Inflected forms of o
The table below gives the inflected forms of o with their accompanying pronouns:
Notes:
  1. Variants ono i and onot ti are common.
  2. Extended variants adding -ho- are also used, so ohonoch chi = onoch chi etc. These extended forms also more like the literary standard forms with the exceptions of 1st pers. sing. and 3rd pers. pl.
  3. A negative variant mo is also in use and is a contraction of dim o. This can be heard as monoch chi = dim ohonoch chi.

Oddiar causes soft mutation and is a compound of o + ar. Oddiar also takes the same inflections as ar, e.g. oddiarno fo. It is basically the opposite of ar and describes motion in the opposite direction of ar. It therefore means 'off' in the sense of 'from upon': Cymer dy bethau oddiar y bwrdd, nei di? 'Take your things off the table, will you?'. Oddiar is not used to translate adverbial use of English 'off', for which Welsh uses i ffwrdd and bant.
Inflected forms of oddiar
The table below gives the inflected forms of oddiar with their accompanying pronouns:

Oddiwrth causes soft mutation and is a compound of o + wrth. Oddiwrth inflects in the same way as wrth, so oddiwrthi hi etc. It means 'from' but is restricted to sentiments sent from one person to another – the opposite of at: Gaethon ni ddim cerdyn oddiwrth dy reini eleni, naddo? 'We didn't get a card from your parents this year, did we?; or Penblwydd Hapus oddiwrth bawb yn y swyddfa 'Happy Birthday from everyone at the office'.
Where a verb of receiving is used – as in the first example above, gan is a possible alternative to oddiwrth.
Inflected forms of oddiwrth
The table below gives the inflected forms of oddiwrth with their accompanying pronouns:

Rhag is a lesser used preposition in colloquial Welsh and its usage is very restricted. Rhag causes no mutations and has the following meanings:
  1. 'from' but only after certain verbs, like atal – 'stop', rhwystro – 'prevent', and gwahardd – 'forbid, prohibit':
  2. # Bydd rhaid ceisio atal y bobol 'ma rhag dod yn rhy agos – 'We'll have to try to stop these people from coming too close''
  3. # Dw i am rwystro chi rhag niweidio'ch hunan – 'I want to try to prevent you hurting yourself'
  4. # Fe waharddwyd y teithwyr rhag mynd ymhellach – 'The travellers were forbidden to go any further'
  5. Rhag is used as part of the conjunction rhag ofn 'in case, for fear that...':
  6. # Dere di ag un yfory hefyd, rhag ofn i mi anghofio – 'You bring one tomorrow too, in case I forget'
  7. It can appear in set expressions such as rhag cywilydd! 'for shame!', which is a less common version of cywilydd arant ti! 'shame on you!'
As a prefix, rhag- usually equates to English 'pre-' or 'fore-': rhagfarn 'prejudice', rhagweld 'foresee'.
Inflected forms of rhag
The table below gives the inflected forms of rhag with their accompanying pronouns:
Note that these inflected forms are often pronounced as rhactha i, rhacthat ti, rhacthi hi etc.

Rhwng, which causes no mutation, means 'between' and its usage is more-or-less the same as its English equivalent. Examples:
  1. Bydd y gêm rhwng Cymru a Lloegr yn cael ei haildrefnu – 'The game between Wales and England will be rescheduled'.
  2. Dewch draw rywbryd rhwng tri a pedwar 'come around between three and four''
Inflected forms of rhwng are used to make idiomatic expressions like Rhyngddat ti a fi... and Rhyngddoch chi a fi... 'Between you and me...'.
Inflected forms of rhwng
The table below gives the inflected forms of rhwng with their accompanying pronouns:
Note that these are often heard as rhyngtha i, rhyngthat ti, etc. Also, variants using the stems rhwngdd-, rhynth- and rhyng- are in use.

Tan, which causes soft mutation, means 'until, till' and is found with time expressions:
  1. Fyddwn ni ffwrdd tan fis Tachwedd – 'We'll be away till November'
  2. 'Dda i 'ma tan hanner awr wedi pedwar – 'I'll be here until quarter past four'
Tan can also be used when taking leave of someone: Tan yfory, 'te! – 'Till tomorrow, then!', Tan hynny! – 'Till then!', Tan y tro nesa! – 'Till the next time!', Tan Ddydd Llun! – 'Till Monday!' etc.
Where English 'until' is used as a conjunction, that is when it is followed by a whole phrase with a verb in it, then nes is the preferred translation:
  1. Na i aros tan ar ôl cinio – 'I'll wait until after lunch'
  2. Na i aros nes iddo ffonio – 'I'll wait until he phones'
However, tan can be heard to be used as a conjunction in some areas, so it is possible to hear Na i aros tan iddo ffonio; but there are also speakers who would consider this to be substandard or "bad Welsh".
Tan has no inflected forms.

Trwy, which causes soft mutation, means 'through' in the spatial sense, e.g. cyllell boeth trwy fenyn – 'a hot knife through butter', edrych trwy'r twll – 'look through the hole'. Trwy also has other uses:
  1. When used with a verbal-noun, it equates to English 'by... ing':
  2. # Ceisiwch ymlacio trwy anadlu'n ddwfn am funud neu ddau – 'Try and relax by breathing deeply for a minute or two'
  3. # Fedrwn ni ennill trwy ganolbwyntio'n fwy ar dactegau – 'We can win by concentrating more on tactics'
  4. When used with time expressions it means 'all' :
  5. # trwy'r dydd – 'all day'

  1. # trwy'r wythnos – 'all week'
  2. # trwy'r flwyddyn – 'all year'
In this sense gydol is sometimes heard with trwy: trwy gydol y flwyddyn 'all year' etc.
Inflected forms of trwy
The table below gives the inflected forms of trwy with their accompanying pronouns:

Tua causes the aspirate mutation and means 'towards' in a spatial sense, but this meaning has been taken over by tuag at in the modern language, except for set expressions like tuag adre 'home'. Its primary use in the modern colloquial language is for conveying approximation. For example, 'about' with both time and quantity expressions: tua naw o'r gloch – ' about nine o'clock', tua pum pwys o datws – 'about five pounds of potatoes'. With expressions of time tua/tuag can be replaced with the compound preposition o gwmpas: o gwmpas naw o'r gloch. Some examples of the use of tua/tuag:
  1. Mae tua hanner y boblogaeth leol wedi ffoi – 'About half the local population have fled'
  2. Mae e tua'r un fath fel arfer – 'It's usually about the same'
Tua/tuag has no inflected forms.

Wrth causes soft mutation and is almost always heard as wth in normal speech has a number of uses:
  1. In purely spatial expressions wrth means 'by' or 'at' where there is a sense of close proximity:
  2. # Wrth y ddesg – 'By the desk'
  3. # Mae rhywun wrth y drws – 'Someone is at the door'
  4. It also means 'by' when used after verbs of knowing or recognising:
  5. # Nes i adnabod ti wrth dy ffordd o gerdded – 'I recognised you by the way you walk'
  6. After dweud 'say, tell' and other similar verbs:
  7. # Beth yn union wedest ti wrth y ferch druan? – 'What exactly did you tell the poor girl?'
  8. When used with a verbal-noun, wrth means 'while..... ing' and refers the action back to the subject:
  9. # Pwy welson ni wrth ddod allan o'r siop ond dy gyn-wraig! – 'Who did we see coming out of the shop but your ex!'
  10. Wrth means 'for' after rhaid 'need'. Rhaid wrth '..... is needed':
  11. # Rhaid wrth gyfaddawdu mewn sefyllfaoedd felly – 'There is a need for compromise in such situations'
  12. # Rhaid wrth gefnogaeth – ' need support; Support is needed'
  13. Wrth is also a conjunction 'as, while':
  14. # Wrth i Iolo ddod allan, es i i mewn – 'As Iolo came out, I went in'
  15. Wrth can form a compound preposition wrth ymyl 'beside'.
Inflected forms of wrth
The table below gives the inflected forms of wrth with their accompanying pronouns:
These inflected forms are routinely shortened to 'tha i, 'that ti etc. in speech in all parts of Wales, especially after forms of dweud/deud:
  1. Mae isio deud 'thyn nhw be' 'dy be', on'd oes? – 'They need telling what's what, don't they?'
  2. Be' wedodd hi 'thoch chi? – 'What did she say to you?'
Some idiomatic uses of wrth:
  1. Wrth + a possessive adjective + bodd means 'delighted' or 'in one's element':
  2. # Dw i wrth 'y modd – 'I'm as happy as can be'
  3. # Mae e wrth ei fodd – 'He's in his element'
  4. The 3rd pers. sing. fem. form wrthi is used with yn + a verbal-noun to mean 'busy.....ing':
  5. # Mae'r plant i gyd wrthi'n codi castell tywod draw fan 'na – 'The kids are all busy building a sand castle over there'

Yn causes nasal mutation and means 'in'. Yn 'in' is a true preposition and must not be confused with the complement marker particle yn seen after the verb bod. It is only used when a definite noun follows. Yn is therefore often seen preceding the definite article or the names of places: yn y car – 'in the car' or yn Llandudno 'in Llandudno'. Compare the difference between the use of yn and mewn: yn yr ardd 'in the garden', but mewn gardd 'in a garden'.
Nasal mutation after yn
Yn alone of the Welsh prepositions causes the nasal mutation, but it undergoes a change itself depending on what follows. Therefore yn often appears as ym and yng, though ym only appears before a word beginning with 'm-' or 'mh-' and yng only appears before words beginning with 'ng-' or 'ngh-' whether this is the result of mutation or not:
  1. ym Mangor – 'in Bangor'
  2. yng Ngheredigion – 'in Ceredigion'
  3. yn Nolgellau – 'in Dolgellau'
  4. yng Ngogledd Cymru – 'in North Wales'
  5. ym Mhwllheli – 'in Pwllheli'
  6. yn Nhalybont – 'in Talybont'
  7. ym Machynlleth - 'in Machynlleth
  8. yn Llandudno – 'in Llandudno'
  9. yn yr Alban – 'in Scotland'
The examples above are all place-names, but the rule holds true for all words following yn. For example, yng nghanol y dre 'in the middle of the town'. Mutation of place names not of Welsh origin is often avoided, but not always. The following are all possible in colloquial Welsh for 'in Camden' :
  1. yng Nghamden
  2. yn Gamden
  3. yn Camden
The phrase 'in Welsh' is always yn Gymraeg, even in the literary language and is never *yng Nghymraeg; it is sometimes heard as yn y Gymraeg, it is because of this definite article being omitted that yn Gymraeg is used and not *yng Nghymraeg.
Inflected forms of yn
The table below gives the inflected forms of yn with their accompanying pronouns:
Note that variants with -d- are often heard instead of -dd-'': ynda i, yndo fe etc., as are variants with no linking element: yna i, yno fe etc.