aren’t many verbs where the basic form, past tense and past participle
forms are all the same. I can think of one or two verbs that end with
-t that do not change. Cut and let would be two
examples. Consider the following:
'I let Roger drive the car whenever he wants to.'
'I let Roger drive because I wasn’t feeling very well.'
'If you hadn’t let him use your credit card, you wouldn’t
now be overdrawn.'
'I always cut my toenails with a hacksaw!'
'I cut my finger when I tried to use my father’s saw.'
'I’ve cut my finger and it hurts!'
your grammar books or dictionaries and see if you can find some more
examples of verbs that do not change.
the rest, verbs are either regular and formed in the past
tense and past participle with an ‘-ed’ ending, or they are
irregular, like ‘build’ in your example, Carmen, which
becomes ‘built’ in both past tense and past participle forms.
Many irregular verbs have different forms for past tense and past
participle. Consider the following:
you can see from the beginning of this alphabetical list, many common
verbs in English are irregular and I am afraid it is a matter of
learning what is correct in each case as there is no clear pattern
are eight more common irregular verbs. Test your knowledge to see
if you can get them all right.
Note that for regular verbs where the past ending is always written
-ed there are three distinct pronunciations in English.
past tense -ed ending is sometimes pronounced /t/,
sometimes /d/ and sometimes /id/. Which we use depends
on which letters the verb ends with in the basic form. If the basic
form ends with /d/ for instance, as in fold, it is
pronounced /id/ in the past tense and past participle form.
it to yourself and listen to how you say folded. If it ends
with /p/ in the basic form, as in clap, then it is
pronounced /t/ in past endings. Say it to yourself and listen
to how you say clapped.
Now try the following exercise. (It is a technique that I learnt
as a dictation exercise from Mario Rinvolucri and Paul Davis.) The
first three examples have been done for you.