_____ worries the doctor most was _______ they could find the cause of the disease.
| A．What; how | B．That; that |
| C．What; what | D．How; what |
Look out! Don’t get too close to the house __________ roof is under repair.
| A．whose | B．which | C．of which | D．what |
Women __________ drink more than two cups of coffee a day have a greater chance of having heart disease than those __________ don’t.
| A．who; 不填 | B．不填; who | C．who; who | D．不填; 不填 |
. 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 |