Though _____ of the danger, he still went skating on the thin ice.
| A．warning | B．to warn | C．warn | D．warned |
Output is now six times ________ it was before liberation.
| A．that | B．which | C．what | D．of which |
"Why did you go to the wrong class, Mr. Wang "
"Well, I forget _______ I was supposed to go to."
| A．which the room | B．which room |
| C．what was the room | D．what room was it |
I don't doubt ________ he'll come.
| A．that | B．if | C．what | D．whether |
Why the explosion occurred was ____the laboratory attendant had been careless.
| A．for | B．because | C．since | D．that |
They came to the conclusion ________ by a computer.
| A．that not all things can be done | B．because of not all things be done |
| C．being not all things can be done | D．because not all things can be done |