The speed limit is the fastest speed you are allowed to drive a car at. 限速是允许驾车的最快速度。

I'm willing to help, within limits. 我愿适当予以帮助。

There is a limit to how much I'm prepared to spend. 我准备花多少钱是有限度的。

7. benefit vt. 有益于 vi. 得益于（常与from, by连用） n. 利益，好处；beneficial adj 有益的

　　The new railway will be a great benefit to the people living here.

　　新建的铁路将给住在这里的人带来好处。

　　I want to buy the dictionary because it is of much benefit to me.

　　我想买这本字典，因为对我大有益处。

　　The rain benefits the plants. = The plants benefit from the rain. 这场雨有益于植物。

　　●用法拓展 be of no benefit =be not beneficial 对...... 没益

　　be of great benefit to = be very beneficial to 对......有益 benefit sb 对某人有益

　　for the benefit of = for sb' s benefit为了......的利益 benefit from 从......中受益

8. combine vt.&vi. (使)联合；结合 combination n. 联合；结合 combined adj. 联合起来的

　 We can't always combine work with pleasure. 我们并不总是能在工作中享受到乐趣。

　●用法拓展 combine with sb./ sth. 与某人某物结合起来 combine A with/and B 使A与B联合起来

重点短语

1. in debt 欠债 "in + n." 表示"在......（情况、状况、状态）中"

　　This young couple is always in debt because they never consider their incomes before buying something.

　　这对年轻夫妇总是负债，因为他们在买东西时从不考虑自己的收入。

　　He has a lot of old debts to meet. 他有许多旧债要偿付。

　　●用法拓展 out of debt不欠债 pay off one' s debts还清债务

in danger 在危险中 in order 井井有条 in surprise 吃惊 in trouble陷入困境，倒霉

in public 当众，公开 in ruins 呈废墟状态 in sight 看见

2．before long不久以后

　　It looks as if it will rain before long. 看起来一会儿就要下雨了。

　　His plan seemed to be too difficult，but before long it proved to be practical.

　　他的计划看起来太困难，但是没多久就被证明是很实用。

　　●用法拓展 long before很久以前 ever since从此以后(用于现在完成时)

3．cut down砍倒(树木)；削减；

　　He cut down a tree with an axe. 他用斧头把树砍倒。

　　●用法拓展cut down on减少......的量 cut in插嘴，插入 cut across打断; 抄近路穿过; 遮断;

　　cut off切断，砍掉；中断，隔断 cut up切碎 cut out剪下；戒除(坏习惯等)

4．earn one's living 谋生