May be or Maybe?

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http://georgeroberts.blogspot.com/2011/10/may-be-ou-maybe.html

May be or maybe? They look almost the same, but maybe is an adverb while may, by itself, is a modal verb. In fact, the adverb maybe originated from the expression "it may be" back in the 14th century.

Maybe + Subject + Verb. Maybe he likes baseball.
Maybe means possibly or perhaps. A sentence with maybe is not complete without a verb. For example: Maybe he likes baseball. The verb here is like. But maybe can be a one-word answer to a question. Are you going to the mall? Maybe. Short answers like this are very common in spoken English.

May + infinitive without to = He may go.
May means "will possibly". He may go to the party = He will possibly go to the party. May belongs to the club of modal auxiliary verbs, which also includes will, would, might, can, could, shall and should, among others. May, like other modals, is followed by the infinitive without to. For example, May I go to a movie tonight? It may rain this afternoon.

Maybe he'll go = He may go
So we can have two sentences with different structures that mean the same thing. Maybe I'll go to a movie tonight = I may go to a movie tonight. Both forms are equally correct and widely used, and both transmit the idea that something is possible but not certain.