This is _________ alarm clock.
—Do you have enough men to carry these chairs? —No. I think we need _______ men.
—Could you tell me ______ ? —By watching English movies.
—______to give back the books to the library before Friday. —OK. I will.
As we all know, a dictionary is a book ______ gives the meaning of words.
—Have you known Mr. Smith for a long time? —Yes, since he ______ to our university.