Sometimes our opinions differ _______ what we choose to observe and how we deal with what we’ve observed
| A．which | B．since |
| C．because | D．because of |
We forbid _____________here. Who permits you_____________？
| A．smoking; smoking | B．smoking; to smoke |
| C．to smoke; to smoke | D．to smoke; smoking |
It’s quite impossible that it will rain tomorrow. But if it _______, I would still go to the park.
| A．should rain | B．would rain | C．rains | D．had rained |
_____ scores of times, but he still couldn’t understand it.
| A．Having explained | B．Having been explained |
| C．Though it was explained | D．It was explained |
--- He was nearly killed by a car once.
--- Oh. when was________ exactly?
--- It was in 2002 __________ he was riding a bike on the drive-way.
| A．this; that | B．that; when | C．that; that | D．this; when |
The students expect there ______ more reviewing classes before the final exam.
| A．is | B．to be | C．being | D．have been |