Boys and girls, the books in the library should______ good care of. A. take B. are taking C. be taken
_______ Peter is old and weak, he still has to work.
The windows must _________ before you leave the room.
I am very sad that I ______ many chances in the last few years.
—Must we clean the classroom now?—No ,you _______.
—____________?—Very well, thanks.