30. He’s making_____great progress in his lessons that everyone else in his class can’t believe it.
| A.So | B.very | C.such a | D.Such | 
The biggest problem for most plants, which ___ just get up and run away when threatened, is that animals like to eat them.
| A.shan’t | B.can’t | 
| C.needn’t | D.mustn’t | 
In crowded places like airports and railway stations, you __________ take care of your luggage.
| A.can | B.may | 
| C.must | D.will | 
The teacher __________ have thought Johnson was worth it or she wouldn’t have wasted time on him, I suppose.
| A.should | B.can | 
| C.would | D.must | 
The weather turned out to be fine yesterday. I __________ the trouble to carry my umbrella with me.
| A.should have taken | B.could have taken | 
| C.needn’t have taken | D.mustn’t have taken | 
You know he is not going to let us leave early if we __________ get the work done.
| A.can’t | B.may not | 
| C.shouldn’t | D.mustn’t |