—How many students are there in the classroom? —  　　　．They are all in the lab．

Scott found_________ difficult to solve the problem.

She sits between________.

— Who will teach _______ oral English next term? Can it be a new teacher?— Perhaps. But our head teacher hasn't told us ________ .

－ I need something for cutting the paper.－ Oh, you want a knife? OK, I'll get ______ for you.