I ________ work out the problem at first, but after my teacher showed me an example, I ________ get the answer easily.
| A．couldn’t; was able to | B．can’t; could |
| C．wasn’t able to; could | D．was able to; was able to |
We've been told the good news, but when and where to go for theexciting paid vacation __________ yet.
| A．are not discussed | B．have not been discussed |
| C．is not being discussed | D．has not been discussed |
In 1948，three American scientists invented __________ transistor, which is __________ small electronic device to control an electric current.
| A．the; a | B．a; a |
| C．the; the | D．a; the |
__________ yesterday, we went out for a walk.
| A．As a fine day | B．It was a fine day |
| C．It being a fine day | D．For it was a fine day |
Peter is a brilliant language learner. Within two weeks, he hasdeveloped a good __________ of Chinese and Japanese.
A. customB. imagination
C. exceptionD command
—How do you know our team will win the race in the final?— __________ We are well prepared for it and do more practice aswell.
| A．Why not? | B．It's my guess. |
| C．It's up to you. | D．I couldn't agree more. |