We have learned that regular verbs of the weak conjugation form their
past tense and perfect participle by adding _ed_ or _d_ to the present
tense form.
Point out how the following verbs form their past tense and perfect
participle:
=Present.= =Past.= =Perfect
Participle.=
mean, meant, meant.
sleep, slept, slept.
say, said, said.
cost, cost, cost.
In some verbs the _ed_ or _d_ of the past tense is sounded like _t_, and
in many cases the spelling has changed to _t_. A few verbs shorten the
vowel of the present; as, _feel_, _felt_, _felt_. Other verbs of this
conjugation change the vowel before adding _d_; as, _tell_, _told_,
_told_; and a number that end in _t_ or _d_ make no change; as, _set_,
_set_, _set_.