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Though great progress has been made in astronomy in the past fifty years, ______ still much that
remains mysterious to astronomers _______ the universe, even the solar system.
[     ]
A. It is; of  
B. there is; about  
C. It is; with  
D. there is; with
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科目：高中英語(yǔ) 來(lái)源：活題巧解巧練·高二英語(yǔ)（上） 題型：022

用所給詞或詞組的適當(dāng)形式填空。

day after day, in the voice of, favorite, 

come up with, look like, before long, 

lose heart, ever since then, one day, operate

1．He went into the forest alone to hunt wild animals. He has never been heard of ________.

2．Football has been my ________ sport since ten years ago.

3．When I came into the room, he cried ________ a duck and everyone laughed heartily.

4．As we were wondering what to do, he suddenly ________ an idea.

5．Though he failed once again to pass the GRE test, he never ________.

6．________ he would sit by the doorway in the hope that she would come around.

7．This shopping center ________ by his uncle.

8．We'll be back to play football with you ________.

9．I can't tell you from your brother. You two ________ each other.

10．________ , when I was sitting in the sun reading, I saw him steal into the room.

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