The research is so designed that once _____ nothing can be done to change it.
| A．begins | B．having begun | C．beginning | D．begun |
I have finished translating a large part of the book, but the rest ___ more difficult.
| A．is | B．are | C．was | D．were |
After the new type of rice was introduced, the farmers produced _______ rice this year as last year.
| A．as twice much as | B．twice as much as | C．twice much as | D．twice as much |
The chairman thought _____ necessary to invite Professor Smith to speak at the meeting.
| A．that | B．it | C．this | D．him |
_____ we were worried about was _______ they could manage to control the pollution.
| A．That; how | B．That; whether |
| C．What; that | D．What; whether |
The manager of the supermarket was so impatient and even rude! I will never go shopping in that supermarket again and __________________.
| A．nor will my friends go. | B．neither my friends will go. |
| C．nor my friends will go. | D．neither will go my friends. |