He is busy writing the article all the morning, only ________ occasionally to have a cup of coffee.
| A．breaking off | B．breaking down |
| C．breaking through | D．breaking up |
—They haven’t finished the work up to now.—Well, they________.
| A．should | B．should have | C．would | D．must have |
It is not like Jack to be unfriendly, so he _________ you when you called.
| A．can’t have seen | B．should not have seen |
C．must not have seen | D．need not have seen |
He used to teach in that university and I _________ ride past it on my way to work.
| A．would | B．could | C．should | D．might |
On Sundays when I was a child, Father and I _______ get up early and go fishing.
| A．could | B．would | C．might | D．should |
—Hurry up, Michael! It’s ten to three.—Goodness me! The class_______. I’ll be late again.
| A．must begin | B．may begin | C．should have begun | D．must have begun |