同学你好，该知识点来自沪江网校《英语零基础直达大学六级全能畅学卡【现金奖励班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学好

1.before
例句：
1. Mary usually reads the new words before【介词,在...之前】 the English class.
玛丽通常在英语课前读单词。
2. Suddenly an animal came before 【介词】him.
突然，一只动物来到他面前。
3. He corrected his mistakes before 【连词】the exam came to an end.
考试结束前，他修改了错误。

2.after
例句：
1. After【介词】a while, the bird flew away from the branch.
过了一会，那只鸟儿从那根树枝上飞走了。
2. An ambulance arrived five minutes after【连词】the accident happened.
事故发生五分钟后，一辆救护车开来了。

3.as
例句：
1. Tom worked as【介词】 a clerk in a bank after graduation.
毕业后，汤姆在一家银行做职员。
2. As【连词，时间状语从句】time goes on, more and more people have realised the importance of protecting the environment.
随着时间的推移，越来越多的人开始意识到环保的重要性。
3. As【连词，原因状语从句】he was ill, he was absent from the class.
因为他生病了，所以他今天没有上课。
4. Young as【连词，让步状语从句，用于倒装结构】 she is, she knows a lot about history.
尽管她很年轻，她对历史却懂得很多。

4.like
例句：
1. Tom is like【介词】 his father in looks.
汤姆的相貌像他父亲。
2. She feels like【介词】 going swimming in the swimming pool.
她想到游泳池去游泳。
3.The weather looks like【介词】 clearing up.
天气好像会放晴。
4. Like 【连词】I said，you're always welcome to stay.
正如我以前所说过的，我永远都欢迎你留下。like i said = as I said
5. She acts like【连词】she owns the place.
她的举动就像那地方是她的一样。

5.till
例句：
1. The meeting lasted from two o'clock till【介词】 six o' clock.
会议由两点一直持续到六点。
2. She didn't return home till【介词，与not搭配】 eleven o'clock.
她11点钟才回家。
3. Keep walking till 【连词】you reach the traffic lights.
一直走到红绿灯为止。
4. I didn't realize what had happened till 【连词】he told me.
直到他告诉我我才意识到出了什么事。

6.until
1. They talked on and on until 【介词】four o'clock in the morning.
他们一直谈到凌晨四点。
2. He did not set foot in England again unti【介词】l 2002.
直到2002年他才再次来到英国。[常用于否定结构中]
3. No further comments will be made on this issue until【连词】 the report is received.
在得到报告之前，就此问题再无进一步评论。
4. If there isn't a winner, the cycle is repeated until 【连词】someone gets a majority of votes.
如无人胜出，整个过程再来一遍，直到有人得到大多数选票。

7.since
1. There have been many changes since【介词】 the war.
从战争到现在发生了许多变化。
2. She has rung me once since【连词，时间状语从句】 she left.
她离家后给我来过一次电话。
3. I've been busy ever since【连词，时间状语从句】 I came back.
自我回来后一直在忙。
4. Since 【连词，既然，由于。原因状语从句】this is so,it's better to accept it.
既来之，则安之。

8.unless
1. Nothing will come of it, unless 【介词】disaster.
此事除了引起灾祸以外不会有什么结果。
2. How do you know what sites to go to unless 【连词】you search the Web?
如果不浏览网页，你又怎么知道该去哪个网址？
3. He won't attend the party unless【连词】 (he is) invited.
如果没有人邀请，他是不会去参加那个聚会的。

9.for
1. They have ordered some equipment for【介词】 the education.
他们已经预定了一些教学设备。
2. Let's go out for【介词】 a walk .
我们出去散散步。
3. She has an eye for【介词】 beauty.
她对美有鉴赏力。
4. He felt no fear, for【连词】 he was a brave man.
他不感到害怕，因为他是个勇敢的人。
5. Comfort him for【连词】 he is sad.
去安慰他，因为他很悲伤。