It was 80 years before Christopher Columbus crossed the Atlantic______ Zheng sailed to East Africa
| A．when | B．that | C．after | D．since |
Edward, you play so well. But I you played the piano.
| A． | didn't know | B． | hadn't known |
| C． | don't know | D． | haven't known |
She brought with her three friends, none of__________ I had ever met before.
| A．them | B．who |
| C．whom | D．these |
I tried phoning her office, but I couldn’t__________.
| A．get along | B．get on |
| C．get to | D．get through |
His sister left home in 1998, and__________ since.
| A．had not been heard of | B．has not been heard of |
| C．had not heard of | D．has not heard of |
What do you mean, there are only ten tickets? There__________be twelve
| A．should | B．would |
| C．will | D．shall |