Finite verbs (main verb) stand after subject and must be conjugated to the subject in simple present tense.
For example: I go fishing. She goes fishing. In this case, "go" the finite verb and must be conjugated follow the subject.
Infinite verbs, in summary, are: can, could,may,might, do*, did*, ...(*:these verb can be finite or infinite). For example:
I can eat a whole chicken. (There are 2 verbs in this sentence. "Can" is the infinite verb and "eat" is the finite one).
May I open the window? ( "May": infinite, "open": finite)
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