as 做连词后面只能跟 clause， 不能跟phrases or nouns

txsnowsea

在复习og。觉得看英文的解释，好像也不那么难了。可是突然看到“as 做连词后面只能跟 clause， 不能跟phrases or nouns”，我又想，连词和介词，究竟该怎么区分啊。
google了一下。。这篇汉字语法，感觉还挺好玩的。大家可以看看。

连词和介词的辨别

现代汉语中连词和介词不易辨别。下面仅以“和”为例，谈谈连词和介词的两种辨别方法。如“他的为人和处事是和他的文化素养分不开的”。这句中共出现了两个“和”字，但这两个“和”字的词性却不相同。前一个是连词，后一个是介词。如何区分呢？
 一、连词前面不带修饰成分，而介词前可以带修饰成分。介词前面的修饰和介词“和”结合在一起往往有多种表现形式。如：连词+“和”、能愿动词+“和”、趋向动词+“和”、时间副词+“和”、时间名词+“和”、介宾短语+“和”等。下面就此举例说明。

  1、哥哥、姐姐和妹妹一起去感赶集。
  2、妈妈和孩子讲笑话。
  例1中“和”前面没有修饰成分，也不能有修饰成分，所以例1中的“和”是连词。例2 中的“和”前面暂时没有修饰成分，但可以把修饰成分加在“和”的前面，如说成“妈妈一边和孩子讲笑话，一边织毛衣”、“妈妈愿意和孩子讲笑话”、“妈妈过来和孩子讲笑话”、“妈妈经常和孩子讲笑话”、“妈妈在屋里和孩子讲笑话”等。
  二、连词连接的两个部分地位平等，前后两个词语互换，句子的意思不会发生变化；介词的前后两个部分，不能调换次序，否则，句子的就会发生根本性的变化。如：
  3、小明和小刚是同班同学。
  4、假日里，老师和同学们打电话。
  例3可以说成“小刚和小明同班同学”。小明和小刚的位置虽然已经调换，但句子的意思没有发生变化，可见例3中的“和”是连词。例4如果换成“假日里，同学们和老师打电话”，句子的意思就发生了变化。原句的“老师”是动作的发出者，在“打电话”的过程中占主动地位。改变了次序后，“同学们”变成了主动者，“老师”成了接电话的人。所以例4中的“和”是介词。
   与“和”字类似的“与”、“跟”、“同”等，在具体语句中出现时年，同样可以用以上介绍的两种方法来辨别。

txsnowsea

还有like 做连词，直接可以跟名词
Like Jack， tolstoi rebelled against。。。。。

lonelyorchid

真诡异……你把这个好好看看不就明白了？

牛津高阶英语词典      
as  
preposition, adverb, conjunction
*preposition
used to describe sb/sth appearing to be sb/sth else: They were all dressed as clowns. ◆ The bomb was disguised as a package.
used to describe the fact that sb/sth has a particular job or function: She works as a courier. ◆ Treat me as a friend. ◆ I respect him as a doctor. ◆ You can use that glass as a vase. ◆ The news came as a shock. ◆ She had been there often as a child (= when she was a child).
*adverb
as ...as ... used when you are comparing two people or things, or two situations: You're as tall as your father. ◆ He was as white as a sheet. ◆ She doesn't play as well as her sister. ◆ I haven't known him as long as you (= as you have known him). ◆ He doesn't earn as much as me. ◆ He doesn't earn as much as I do. ◆ It's not as hard as I thought. ◆ Run as fast as you can. ◆ We'd like it as soon as possible.
used to say that sth happens in the same way: As always, he said little. ◆ The 'h' in honest is silent, as in 'hour'.
*conjunction
while sth else is happening: He sat watching her as she got ready. ◆ As she grew older she gained in confidence.
in the way in which: They did as I had asked. ◆ Leave the papers as they are. ◆ She lost it, just as I said she would.
used to state the reason for sth: As you were out, I left a message. ◆ She may need some help as she's new.
used to make a comment or to add information about what you have just said: As you know, Julia is leaving soon. ◆ She's very tall, as is her mother.
(written) used to say that in spite of sth being true, what follows is also true
--------------------------------------------------------------------------------
WHICH WORD?
as / like
You can use both as and like to say that things are similar.
Like is a preposition and is used before nouns and pronouns: He has blue eyes like me.
As is a conjunction and an adverb and is used before a clause, another adverb or a clause beginning with a preposition: She enjoys all kinds of music, as I do. ◆ Repeat these five steps, as in the last exercise.
In informal English like is frequently used as a conjunction or an adverb instead of as: Nobody understands him like I do. ◆ I don't want to upset him again like before. It is also used instead of as if:
It looks like we're going to be late. These uses of like are common but are not considered correct in formal written English.
You will find more help on the use of as and like in the entries for particular verbs, such as act, behave, etc.