The paint came off as a result of _________ to the rain. I must repaint the windows before they go rusty.
| A．contribution | B．discrimination |
| C．exposure | D．exhibition |
______ we gave him something to eat, he would save it up for his little sister.
| A．Whatever |
| B．However |
| C．Whenever |
| D．Whichever |
--All students must hand in your exercises right now.
-______ We don’t have enough time to finish them.
| A．It doesn’t make sense. |
| B．You said it. |
| C．Forget it. |
| D．It’s up to you. |
Smoking is one of the ______ cause of cancer, killing millions of people each year.
| A．major |
| B．similar |
| C．appropriate |
| D．casual |
______ his father’s letter, he decided to make a call to him.
| A．Having seen |
| B．Having been seen |
| C．Not having received |
| D．Having not received |
Last week, Susan and David, ______ our university’s student association, met the Chinese guests at the New York airport.
| A．to present |
| B．representing |
| C．represented |
| D．having represented |