—How about paying a visit to Mr. Richardson, our former history teacher?
—Good idea. I will e-mail him today so he ___ know ___ to expect us.
| A．may,when | B．would, why | C．will, how | D．shall, why |
John's success has nothing to do with good luck. It is years of hard work _______has made him a great scientist today.
| A．that |
| B．when |
| C．which |
| D．why |
It was 80 years before Christopher Columbus crossed the Atlantic______ Zheng sailed to East Africa
| A．when |
| B．that |
| C．after |
| D．since |
It was not until near the end of the letter ______ she mentioned her own plan.
| A．where |
| B．that |
| C．why |
| D．when |
It was only after he had read the papersMr. Gross realized the task before him was extremely difficult to complete.
| A．when |
| B．that |
| C．which |
| D．What |
An awful accident, however, _____occur the other day.
| A．does |
| B．did |
| C．has to |
| D．had to |