—How was your climbing Mount Huang?
---I didn’t believe I could do it __________I got to the top.
| A．until | B．while |
| C．after | D．because |
Jim’s shirt is made _____ silk , and it’s made ______ china.
| A．in, of | B．from, of | C．of , in | D．from , in |
No smoking, please. It’s ____ the rules.
| A．against | B．for | C．on | D．at |
Although we are young, ______ we can still do something to help them.
| A．but | B．/ | C．and | D．however |
It is necessary _____ something to protect our environment.
| A．do | B．to do | C．does | D．doing |
If it ______ tomorrow, I’ll go hiking with my friends.
| A．won’t rain | B．will rain | C．doesn’t rain | D．rains |