Though ________ to see us, the professor gave us a warm welcome.
| A．surprising | B．was surprised |
| C．surprised | D．being surprised |
Tom kept quiet about the accident _______lose his job.
| A．so as not to | B．so not as to | C．so as to not | D．not so as to |
There was a terrible noise _______ the sudden burst of light.
| A．followed | B．to be followed | C．following | D．being followed |
The sentence needs _______ once more.
| A．explained | B．explaining | C．being explained | D．to explain |
The computer centre, _______ last year, is very popular among the students in this school.
| A．open | B．opening | C．having opened | D．opened |
Rather than _______ on a crowded bus, he always prefers _______ a bicycle.
| A．ride; ride | B．riding; ride | C．ride; to ride | D．to ride; riding |