By the late 1960s, their style of music _____ completely.
| A．changed | B．have changed |
| C．had changed | D．was changed |
. Will you be able to attend the lecturenext week?
| A．giving | B．given | C．to be given | D．being given |
.An exhibition of paintings ____ at the museum next week.
| A．are to be held | B．is to be held |
| C．are holding | D．will hold |
Every possible means ____, but none ____ successful．
| A．has tried; has proved | B．tried; proves |
| C．has been tried; proves | D．is being tried; is proved |
.The question he asked is hard ____ ．
| A．for answer | B．to answer | C．to be answered | D．answering |
.By the end of last year, another new gymnasium ____ in Beijing.
| A．would be completed | B．was being completed |
| C．has been complete | D．had been completed |