This resource is provided by AmeriCymru and is intended for Welsh learners who are not yet ready to commit to a full time course. With Croeseiriau Cymraeg you can devise your own schedule and learn at your own pace. Before you start please go to this page: Croeseiriau Cymraeg and read the 'Introduction' and 'How to Use' sections.

If you are ready to commit to a full time course we recommend the following options:

AmeriCymraeg This is an online course with tutor John Good, which is offered in two-month terms. Go here for more information and to register: AmeriCymraeg

SSIW Want to learn quickly? Then you might want to check out the SSIW High Intensity Language Program here: SSIW

Online Welsh language course





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Tybio - To Suppose , To Presume

  • tybio - to suppose , to assume

    sample sentences:

    Mae'n rhaid i ni groesi i'r ynys . - We have to cross to the island.

    Dwi'n tybio bod yn rhaid i ni .
    - I suppose we must.

    Image: ...Ynys Sili 


    mutant.jpg In the sample sentence above on this page you will observe that the spelling of one word ( groesi ) differs from the spelling on the relevant Geiriadur listing page ( Croesi - To Cross ). Be not alarmed!

    This happens because:-

    "Welsh, as with all other Celtic languages, often sees changes made to the beginning of words depending on the word that precedes it, or the role it plays in the sentence. These changes are known as "mutations", of which Welsh has three distinct types. Common situations in which a mutation may occur are when a word follows a preposition, possessive, or number."

    The three types of mutation are:-

    Soft Mutation

    Nasal Mutation

    Aspirate Mutation

    The three links above will take you to further information about these commonly occurring mutations.

    Most Welsh courses and teachers advise students not to worry too much about this at the outset. Fluent speakers will understand you if you forget to mutate a letter. With practice this will come naturally and there is perhaps, no need for beginning learners to make a conscious effort to apply these rules.

    However, if you wish to acquaint yourself with the rules early on you could look out for the 'Mutant Alert' notice on the vocabulary pages and use these as an opportunity to refresh your knowledge by checking the above links.

    Spot the Mutation: The mutation above is an example of a ........... mutation?



    Dwi'n tybio - I am supposing

    Wyt ti'n tybio - You are supposing (familiar)

    Mae e'n tybio / Mae hi'n tybio - He / She is supposing

    Dyn ni'n tybio - We are supposing

    Dych chi'n tybio - You (plural) are supposing (also singular formal)

    Maen nhw'n tybio - They are supposing




    Dwi ddim yn tybio - I am not supposing

    Dwyt ti ddim yn tybio - You are not supposing (familiar)

    Dydy e ddim yn tybio / Dydy hi ddim yn tybio - He / She is not supposing

    Dyn ni ddim yn tybio - We are not supposing

    Dych chi ddim yn tybio - You (plural) are not supposing (also singular formal)

    Dyn nhw ddim yn tybio - They are not supposing




    Ydw i'n tybio? - Am I supposing?

    Wyt ti'n tybio? - Are you supposing? (familiar)

    Ydy e'n tybio / Ydy hi'n tybio? - Is he / Is she supposing?

    Ydyn ni'n tybio? - Are we supposing?

    Ydych chi'n tybio? - Are you (plural) supposing? (also singular formal)

    Ydyn nhw'n tybio? - Are they supposing?




    Ydw i'n tybio? - (Nac) Wyt / (Ydych - formal)

    Wyt ti'n tybio? - (Nac) Ydw

    Ydy e'n tybio / Ydy hi'n tybio? - (Nac) Ydy

    Ydyn ni'n tybio? - (Nac) Ydyn / Ydych

    Ydych chi'n tybio? - (Nac) Ydyn / (Ydw - formal)

    Ydyn nhw'n tybio? - (Nac) Ydyn


    N.B. 'Wyt ti' is the familiar form of the 2nd person and should be used only when addressing close friends, family members and animals. 'Dych chi' is the polite form and should be used in all other instances.