In January, 2004, the United States successfully launched “Spirit”, a Mars Exploration Rover, _____ a new milestone in the history of mankind.
| A．it marked | B．marking | C．marked | D．to mark |
Being League members, ___ we ought to work hard at our lessons;___ we ought to take an active part in social activities.
| A．on one hand…on other hand | B．on the one hand….on the other hand |
| C．on the one hand…on the other | D．B and C |
___ the clock structk twelve. I got home with my brother.
| A．As | B．While | C．When | D．Since |
____ for a bus, I was reading a magazine.
| A．While was waiting | B．While I waiting | C．While I am waiting | D．While waiting |
Knowing how long the test would last, the students who finished ____ back and waited until the end of the exam.
| A．settle | B．settled | C．settling | D．to settle |
The captain ordered the crew to throw ____ the side of the ship all heavy guns and even stores in order to raise the boat in the water.
| A．on | B．through | C．across | D．over |