7.---Mary, you didn’t show up at the meeting last week?
---No, I________, but my son had a sudden fever and I had to stay at home to take care of him.
| A．didn’t | B．was going to | C．had to | D．wouldn’t |
.A man may usually be known by the books he reads _______ by the friends he keeps.
| A．as well as | B．as if | C．as soon as | D．as usual |
I _______ to help you but I was not able to spare any time.I _______ a paper last night and I'll have to finish it today.
| A．wanted; have been writing | B．have wanted;wrote |
| C．had wanted; wrote | D．had wanted;was writing |
There are so many books! It is not easy for us to decide what to take and what to_______.
| A．take on | B．pick up | C．leave behind | D．work out |
When I try to understand _______ that prevents so many Americans from being as happy as one might expect, it seems to me that there are two causes.
| A．why it does | B．what it does | C．what it is | D．why it is |
The science of medicine, _______ progress has been very rapid lately, is perhaps the most important of all the sciences.
| A．to which | B．in which | C．Which | D．with which |