(1) 作为介词，like侧重比较；as侧重同一性，意味着属于一类或完全相似。
- He is of a cool temper like his father.
他脾气冷静，像他父亲。 - He is of as cool a temper as his father.
他的脾气与父亲一样冷静。(意味着不仅脾气相同，而且程度也一样) - He does his job like a skilled worker.
他工作起来就像一个技术熟练的工人。 - He does his job as a skilled worker.
他工作起来就与一位熟练工人一样。(意味着与一个技术熟练的工人做得一样好) - He worked very hard all day like a slave.
他像奴隶一样整天拼命工作。 - He worked for their family as a slave for fifteen years.
他为他们家做了15年奴隶。
(2) 美国人常把like用作连词as，后接从句。
- Please do it like ( =as ) I do.
照我做的那样来做吧。 - Nobody else loves you like I do, baby.
孩子，谁也不会像我这样爱你。
(3) 美式英语中还常用like代替as if, as though。
- It rained like the skies were falling.
雨下得就像天要塌了一般。 - She sat there eating cream cakes like there was no tomorrow.
她坐在那儿吃着奶油蛋糕，仿佛没有明天似的。
(4) ①as用作连词表示“像，如，正如，按照，依照”时，常引导方式状语从句。
- I did as he asked, and he said he was satisfied with my work.
我按照他要求的去做了，他说他对我的工作感到满意。 - I want you to tell my friend your interesting experience exactly as you have told it to me.
我想让你把你有趣的经历告诉我的朋友，就像你把它告诉我一样。 - There is great disorder, as the newspapers will have told you.
那里一片混乱，正如报纸上将会告诉你的一样。
②as引起的从句常可用省略形式。
- Everything had happened exactly as (had been) expected.
一切恰如预期的那样发生了。
③as常引起分词短语作状语。
- As expected, the afforestation movement rapidly spread.
就如预期的那样，植树造林运动迅速展开。 - Owing to the rain, the game will not take place as advertised.
由于下雨，比赛将不能像广告上说的那样如期进行。 - As variously estimated, the Indians numbered from 14 million to 40 million in Columbus' times.
根据各种各样的估计，印第安人在哥伦布时代的人数为1 400万到4 000万之间。
④as有时引起从句作表语。
- Our attitude is still as we expressed it in the 1942 agreement on Iran.
我们的态度仍如我们在1942年对伊朗的协定中所表示的那样。 - The house is just as it was two hundred years ago.
这所房子与200年前一模一样。
⑤在正式的书面语中，as有时接疑问句的词序和结构(倒装)。
- He was a Catholic, as were most of his friends.
他是位天主教徒，正像他的大多数朋友一样。 - He believed, as did all his family, that the King was their supreme lord.
就与他的家人一样，他认为国王是他们至高无上的君主。
⑥as还可引起下面这类从句。
- Sophia was not unconscious, as could be judged from her eyes .
就如从她的眼睛可以判断的一样，索菲娅并非毫无意识。 - As was expected , we performed the task with great success.
正如预期的一样，我们非常成功地履行了任务。 - She was a teacher, as/which I knew from her manner .
她是位老师，这一点我从她的举止上就能看出来。
