This book must belong to because it has my name on its front page.

Is this the reason _____ at the meeting for his carelessness in his work?

That T-shirt with Yao Ming’s picture on it ________ belong to David. He admires him a lot. —No, it ________ be his. He hates black color.

I ______ much progress in my English study since last term.

Thanks _____ taking care of my cat.[ ]