I really don't know how to thank you, but for your help, I ________ my lost necklace.
| A．couldn't have found | B．mustn't have found |
| C．couldn't find | D．wouldn't find |
He _______ sleep, although he tried to, when he got on such a hunt for an idea until he had caught it.
| A．wouldn’t |
| B．shouldn’t |
| C．couldn’t |
| D．mustn’t |
—You needn’t take an umbrella. It isn’t going to rain.
—Well. I don’t know. It _______ do.
| A．might |
| B．need |
| C．would |
| D．should |
Cars do cause us some health problems—in fact far more serious _______ than mobile phones do.
| A．one |
| B．ones |
| C．it |
| D．those |
Her mother was ill so she had to look after her________.
| A．day and night |
| B．day by night |
| C．day after night |
| D．day in night |
You’ll have to wait for one more week,________ the manager will be back from his trip.
| A．after |
| B．while |
| C．when |
| D．since |