_________ is known to all，good friends _________ happiness and value to life.
| A．It； add | B．As； add | C．It； add up | D．As； add to |
A recent survey ___ that the majority of people are worried about the present high price of apartments in cities.
| A．indicates | B．includes | C．imagines | D．improves |
Thousands of young college students have ___ the job, because it provides a high salary, a long paid vocation every year and many other attractive benefits.
| A．applied for | B．turned down |
| C．threw away | D．complained of |
Don’t forget to bring a dictionary next class.
___. I didn’t catch what you said.
| A．Never mind | B．I beg your pardon |
| C．That’s right | D．I’m not sure |
Carbon dioxide ___ from burning fuels is the most common of the so-called greenhouse gases.
| A．producing | B．having been produced |
| C．to be produced | D．produced |
Father finally came back home, which I ___ forward it.
| A．had been looking | B．have been looking |
| C．looked | D．have looked |