—Who______ it be that is knocking at the door?
—It ______ be Father, but I’m not sure.
| A．can; must | B．can; may | C．must; can | D．may; must |
Our English teacher requested that the homework _______ tomorrow morning.
| A．would be handed in | B．be handed in | C．hand in | D．must be handed in |
Is this the reason ___________ at the meeting for his carelessness in his work?
| A．he explained | B．what he explained | C．how he explained | D．why he explained |
.Whenever we are in ________ , we must never lose ______ , but try to think of the way out.
| A．the trouble; our heart | B．troubles; hearts | C．trouble; heart | D．trouble; our heart |
The farm ______ we see today is no longer the one ______ it was ten years ago.
| A．that; that | B．where; that | C．where; what | D．which; which |
______ of the land in that district _______ covered with trees and grass.
| A．Two-fifth; is | B．Two- fifth; are | C．Two-fifths; is | D．Two-fifths; are |