Children must _______ road safety before they are allowed to ride a bike on the road.
| A．instruct in | B．instruct | C．be instructed in | D．be instructed |
It was ______ computer games that cost the boy a lot of time that he ought to have spent on his lessons.
| A．to have played | B．playing |
| C．played | D．having played |
______ a reply, he decided to write again.
| A．Not receiving | B．Receiving not |
| C．Not having received | D．Having not received |
The first textbooks ______ for teaching English as a foreign language came out in the 16th century.
| A．having written | B．to be written |
| C．being written | D．written |
Most common people desired that more attention _______ public opinion.
| A．pay to | B．paid to |
| C．was paid to | D．be paid to |
Beijing isn’t what it used to be. The last decade _______ great changes in the city images.
| A．witnessed | B．was witnessed |
| C．has witnessed | D．had witnessed |