When do you use maybe and when do you use may be?
This is a common mistake for students learning English (and sometimes native speakers too!).
The simplest explanation is:
Maybe = perhaps
May be = is possibly
- Our boss was sick yesterday so he may be absent from work today. Maybe our meeting will be postponed until he comes back.
- He may be creative or maybe he is just crazy.
A bit more detail…
MAYBE
Maybe is an adverb that means perhaps.
- Maybe it will stop raining soon. = Perhaps it will stop raining soon.
- A: I thought Suzy would be here by now. B: Maybe she forgot.
MAY BE
May is a modal verb which indicates possibility.
- He may be lost = It is possible that he is lost
- This may be the best website = This is possibly the best website
After may be we usually have an adjective, a noun or a verb (in ING form)
- He may be crazy. (may be + adjective)
- He may be a genius. (may be + article + noun)
- He may be trying too hard. (may be + verb ING form)
Remember that May is similar to Might
- He may be late = He might be late
Maybe you have a better explanation than this. 
{ 1 comment… read it below or add one }
Excellent explanation! Many students are, understandably, confused about the use of maybe and may be. Well done.