—Who has broken the window in my room?
—Who else it but your naughty son!
| A．could do | B．could have done | C．might do | D．must have done |
No one _____ be more generous; he has a heart of gold.
| A．could | B．must | C．dare | D．need |
If he had spent more time practicing speaking English before, he _____ able to speak it much better now.
| A．will be | B．would be | C．has been | D．would have been |
--Why are your eyes so red? You _______ have slept well last night.
---Yeah, I stayed up late writing a report.
| A．can't | B．mustn't | C．needn't | D．won't |
When I was a child, I ______ watch TV whenever I wanted to.
| A．should | B．could | C．must | D．need |
I should not have laughed if I ______ you were serious.
| A．thought | B．would think | C．had thought | D．have thought |