Are my sentences grammatically correct?

[Ayon Khan]

1. Rony must have that book.
2. Rony must be having that book.
3. He may have a guitar.
4. He may be having a guitar.

I know point 1 and 3 are corrects. But are point 2 and 4 correct? Can you give me grammatical explanation about those sentences?

 

[emsr2d2]

1. Rony must have that book.
2. Rony must be having that book.
3. He may have a guitar.
4. He may be having a guitar.

I know [STRIKE]point[/STRIKE] sentences 1 and 3 are [STRIKE]corrects[/STRIKE] correct no full stop here but are [STRIKE]point[/STRIKE] sentences 2 and 4 correct? Can you [STRIKE]give me grammatical explanation about those sentences[/STRIKE] tell me why?

Note my corrections above. You are right that sentences 2 and 4 don't work. Some verbs don't work (aren't used) in the continuous. You can find out more in a good grammar book or online.

By the way, "Rony" is a very unlikely spelling of a name in English. "Ronnie" is a fairly common man's name. "Romi/Romy" are relatively uncommon women's names, but they do exist.