The president was so absorbed in his work that not a sound __________.
| A．did she dare to make | B．dared she to make |
| C．she dared make | D．she did dare to make |
The truth, sir, is that the old man _______ across the road when my car hit him.
| A．was to walk | B．had been walking | C．walked | D．was walking |
To find the street where I lived in my childhood is no easy task because the city ______ so rapidly all these years.
| A．is changing | B．has changed | C．will have changed | D．will change |
----She must have gone back to the valley.
----No, she _____. The entrance to it was nowhere to be found.
A mustn’t B needn’t C couldn’t D hadn’t
She is late. What _____have happened to her?
A should B must C can D would
.We were all waiting for you .You _____for the seaside by yourself without leaving a message.
| A．mustn’t leave | B．shouldn’t have left | C．couldn’t have left | D．needn’t leave |