Grammar questions (Song)

1.I want to know the differences between "as" and "which" in attributive clause
 for example: He made a long speech, as we expected.
             Can we replace "which" with "as"?

2.In attributive clause, can we replace "which" with "that" in all circumstance?
 for example: Football is a game which(that) is liked by most boys.

3.What is the difference between "try doing" and "try to do".


I answer the question from what I learned six years ago. It may not be precise and even not be right.

When it comes to restrictive attributive clause and be used after the word( such, as, the same...), you must use "as" to start a attributive clause. And in the other situation "which" can be used.

When it comes to non-restrictive attributive clause, "as" and "which" is the same expect the following situation:
1. The attributive clause starts before the main sentence. Example: As is known to everybody, the moon travels round the earth once every month.
2. "As" has the meaning of "as expected" but "which" doesn't.
3. "As" is always uesd to explain a sentence or a long phrase.
4. "As" only can be used when the verb in attribute clause is linking verb.

The difference between "that" and "which" is "that" can be used in most situations. However "which" can not.

"Try to do" means do something and finish that by all means.
"Try doing" means do something just for trying and fun.

Guo