根据括号中所给的汉语写出单词。
Those boys like playing hide-and-seek and often hide __________(在…之中) the trees.
How beautiful she is and her skin is as _________(光滑的)as silk.
She is looking forward to         (收到) letters from her friends.
The heavy smog makes it more difficult for us to see traffic signs _________(清楚地).
After several         (星期) study, we will have our senior high school entrance exam.
B）根据句子意思，用括号中所给单词的正确形式填空。
In the morning, taking a walk and _________(breathe) some fresh air are good for your health.
He was ___________(terrible) hurt and had to stay in hospital for a long time.
Many _________(wood) houses have been built for the tourists in this area recently.
Mr. Brown _____________ (prefer) hiking to running when he was in his twenties.
Tian’anmen Square is always filled with __________(visit) on National Day.