What is even more important is_____ the earth cooled down, water began to appear on its surface.
| A．that | B．that as | C．which | D．which as |
He told me the news, believe it or not, ______ he had earned $1 000 in a single day.
| A．that | B．which |
| C．as | D．because |
I think, though I could be mistaken, ______ she liked me.
| A．who | B．which |
| C．that | D．what |
Everyone knows, perhaps except you, _______ your girl-friend is a cheat.
| A．who | B．which |
| C．that | D．what |
Someone is ringing the doorbell. Go and see ______.
| A．who is he | B．who he is |
| C．who is it | D．who it is |
It was ten o’clock _____ he came back home.
| A．when | B．that |
| C．since | D．after |