_________ 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 |
With a lot of problems __________, the new government is now having a hard time.
| A．settling | B．to settle | C．settle | D．having settled |
Though I’ve tried very hard to improve my English, by no means ___________with my progress.
| A．the teacher is not satisfied | B．is the teacher not satisfied |
| C．the teacher is satisfied | D．is the teacher satisfied |
Science and technology have in important ways __________ the improvement of agricultural production.
| A．contributed to | B．resulted from | C．carried off | D．handed over |
Mr. Han, my neighbor, is always helping those who are in trouble without expecting anything __________.
| A．in turn | B．in return | C．in detail | D．in addition |
He is very sick. I insist that a doctor __________ immediately.
| A．has been sent for | B．sends for | C．will be sent for | D．be sent for |