He did not regret saying what he did but felt that he it differently.
| A． | could express | B． |
would express
|
| C． | could have expressed | D． |
must have expressed
|
—Turn off the TV, Jack. ____your homework now?
—Mum, just ten more minutes, please.
| A．Should you be doing | B．Shouldn't you be doing |
| C．Couldn't you be doing | D．Will you be doing |
. —What do you think we can do for our aged parents?
—You ________ do anything except to be with them and be yourself.
| A．don’t have to | B．oughtn’t to | C．mustn’t | D．can’t |
His lack of professional knowledge _______for the failure of the experiment.
| A．accounted | B．explained | C．counted | D．contributed |
Not believing their eyes, the visitors on the spot _______ the flying plane, doing some most difficult and dangerous tricks in the sky.
| A．glared at | B．stared at | C．glanced at | D．caught sight of |
Many festivals are held _______ our ancestors for their contribution to the world.
| A．in honor of | B．in the honor of | C．in memory to | D．in the memory of |