A: Where's Harry?#
B: He may be in his room. I'm not sure.#
A: Where will he go?#
B: He may go to the cinema. I'm not sure.#
A: Why is he late?#
B: He may be busy. I'm not sure.#
A: What is he doing?#
B: He may be reading. I'm not sure.#
A: Why was he late?#
B: He may have been busy. I'm not sure.#
A: What was he doing?#
B: He may have been reading. I'm not sure.&