单项选择（每题1分）
—Listen！It is raining.
—Oh， really！ I______ it at all.
| A．didn’t realize | B．don’t realize |
| C．haven’t realized | D．hadn’t realized |
_______ the news, so far, has been good, there may be bad days ahead.
| A．When | B．While | C．If | D．As |
Not until the train pulled into the next station ________ her suitcase gone.
| A．Mary had found | B．had Mary found |
| C．Mary found | D．did Mary find |
He hurried to the booking office only ______ that all the tickets had been sold out.
| A．told | B．to tell | C．to be told | D．telling |
The problem lies_______ we are now giving him a fish, not teaching him to fish.
| A．in that | B．in which | C．on which | D．at which |
When ____ comes to saving energy, big changes start with small steps, like turning off the lights.
| A．that | B．this | C．it | D．one |