____ makes mistakes must correct them.
| A．Who | B．What | C．Whoever | D．Whatever |
Contemporary English is quite different from Old English. There has never been a year____the language was not changing.
| A．that | B．when | C．for | D．until |
To help a friend solve the problem troubling him,.
| A．a friend should be made known of his difficult situation |
| B．a man should be equipped with the kind of knowledge required |
| C．nothing is better than offering of knowledge required |
| D．keeping one’s promises is most important |
Not until all the fish died in the riverhow specious the pollution was.
| A．did the villagers realize | B．that the villagers realized |
| C．the villagers did realize | D．didn’t the villagers realize |
a reward of $1,000 will be given to can provide any clues to the case which has been investigated by the police for nearly half a year.
| A．whoever | B．whomever | C．anyone | D．who |
—What caused the party to be put off?
—_________the invitations.
| A．Tom delayed sending | B．Tom’s delaying sending | C．Tom delaying sending | D．Tom delayed to send |