You can get the best result ________ you carry out the experiment under the desired conditions.
| A．what if | B．even if | C．only if | D．as if |
____under the tree was a charming girl aged about seventeen or eighteen．
| A．Sat | B．Sitting |
| C．To sit | D．Sit |
—Will you attend the meeting this afternoon？
—But I ________ told anything about it．
| A．haven't been | B．am not |
| C．wasn't | D．won’t be |
He wrote a long letter ______ he explained what had happened in the accident．
| A．what | B．which |
| C．where | D．how |
—The constant noise around here______ me crazy！
—Calm down．It’s no use complaining．
| A．drove | B．drives |
| C．is driving | D．had driven |
—Hurry up！There’s a bus coming！
—Why run？There will be_____one in two or three minutes．
| A．another | B．other |
| C．the other | D．any other |