“Mike is often absent from class.” “Tell him he _     _ answer for it if he goes on behaving like that.”

— Mike, is this your eraser? — No, it’s not ______.  Maybe it’s __________. 

I was really busy these days, otherwise I _______ to your birthday party last night.

Lora，you ____________ leave all your books on the floor like this!

 —Tom can’t find his gloves. Are these blue gloves his?      —No, they ______ be his. His gloves are black.