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Gallwn - Could

  • gallwn* - could

    sample sentence: Gallen ni fynd i'r traeth yfory os yw 'r tywydd yn braf .   - We could go to the beach tomorrow if the weather is fine.

    Image: ...mynd i'r traeth

    * Gallwn is used to mean 'could' in the southern Welsh dialect while medrwn is used in the north.

  • This is the conditional form of gallu (can, to be able) and means 'could'. It uses similar endings to other auxiliary or modal verbs e.g. dylwn -should , byddwn - would and hoffwn - would like. Gallwn is not followed by “yn + verb noun” but only the verb noun. It also causes a mutation in the verb that follows (see examples below).

    Gallwn i fynd i siopa cyn cinio . - I could go shopping before lunch.

    Gallen nhw gyrraedd yfory . - They could arrive tomorrow.

    To say 'I could have', 'you could have' etc put fod wedi after gallwn . The following verb does not mutate. See full forms below.


    gallwn i                           i could                  
    gallet ti                            you (familiar) could                  
    gallai e/o                         he could                    
    gallai hi                           she could                
    gallen ni                          we could               
    gallech chi                      you (formal & plural) could               
    gallen nhw                      they could   


    allwn i ddim                    i couldn't
    allet ti ddim                     you (familiar) couldn't
    allai e/o ddim                  he couldn't
    allai hi ddim                    she couldn't
    allen ni ddim                   we couldn't
    allech chi ddim               you (formal & plural)couldn't
    allen nhw ddim               they couldn't


    allwn i?                               could I?
    allet di?                               could you?
    allai e/o?                             could he?
    all hi?                                  could she?
    allen ni?                              could we?
    allech chi?                          could you?
    allen nhw?                          could they?


    allet/na allet, gallech/na gallech
    gallwn/na gallwn
    gallai/na gallai
    gallai/na gallai
    gallech/na gallech, gallen/na gallen
    gallwn/na gallwn, gallen/na gallen
    gallen/na gallen


    Gallwn i fod wedi                            i could have
    Gallet ti fod wedi                             you (familiar) could have
    Gallai hi fod wedi                            she could have
    Gallai e or Gallai o fod wedi           he could have
    Gallen ni fod wedi                           we could have
    Gallech chi fod wedi                       you (formal & plural) could have
    Gallen nhw fod wedi                       they could have

    The 'g' is dropped in the negative form e.g. Allwn i ddim fod wedi - I couldn't have


    mutant.jpg In the sample sentence above on this page you will observe that the spelling of one word ( fynd ) differs from the spelling on the relevant Geiriadur listing page ( Mynd - To Go ). 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?