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The modal verbs are
will, would, shall, should, can, could, may, might, and
must.They always occur exactly as written above. No endings such as
s or
ed or
ing are ever used, so you can't have forms like
shoulds, canned, or
musting. And you can't have a full infinitive form either, such as
to shall or
to might.
rods“When used with model modal verbs (except ought), main verbs always remain in the infinitive without to.”
It means that the verb following one of those nine modal verbs shown above is always the dictionary form (also called the base form).
may go, could see, must know, should find, would do
Never: may to go, could to see, must to know, should to find, would to do.
(
ought is basically another way of saying
should, and in this case you use the word
to, like this:
ought to go, ought to see, and so on.)
CJ