做某事是．．．（的）

It + be 动词+名词/形容词/一般动词+ to 动词原形+其他

eg: It is good for you to read English in the morning.  晨读对你有益处。

解析：It 是形式主语，后面的不定式是该句型真正的主语。

1. It is good for you to take exercise every day. 每天做运行对你的健康有益。

2. It is happy thing to make a profit by investing in the stock market. 投资股票市场赚了钱是件很开心的事。

3. In the peak season, it is necessary to make hotel reservations. 在旺季，预定好酒店是有必要的。

4. It is good for you to quite smoking. 戒烟对你而言是件好事。

5. It is good for you to use paper bags instead of plastic bags. 使用纸袋来代替塑料袋对我们是有益的。

6. It is not necessary to pay the bill in advacne. 没有必要先付款。

7. It is good for her to do her homework carefully. 认认真真地做功课，对她而言是有用的。