He didn’t devote his time to his study，did he?—．As a result，he failed all the final exams．

Knowledgeable as he is, the expert was unwilling tooffer advice to ______ he thought was not qualified.

____, Tom. Is this your pen—No, it isn’t. I think it’s ____.

Students _________ to use theirdictionaries when they _________ an English test.

This singer sang many songs, ________ some of Liu Huan’s.