3.表示缘由的介词
for常常表示褒贬、奖惩是什么原因或心理缘由。
They will reward you for your help.
due to常常用来引导形容词性的短语，作定语或表语。
Mistakes due to carelessness may have serious consequences.
from和out of常常表示动机或缘由；through表示消极或间接是什么原因。
He feels weak from lack of sleep.
He broke down through overwork.
4.表示目的的介词
for表示拟定的接收人或目的；to表示实质的接收人或目的。
I bought the gift for my little sister.
I gave the gift to my little sister.
for和to都可以引导目的地。For跟在含有出发或开始意义的动词后，如：leave， set out，start， depart， sail等；to跟在含有人来人往地行动的意义的动词后，如：go， come， run ，walk，move， fly， drive， ride等。
We have left for Hong Kong.
He flew to America via Hong Kong.
at表示起因；on表示依据。
She is quite pleased at his help.
Ken1 was arrested on a charge of that.
at还可引导行为的目的或精力的集中点。
He shot at the bird.
5.表示关于的介词
一般about用于比较随意的谈话或非正式的文体；on用于正式的讲话、著作或报告中；of用于动词talk， read， know， say， hear， boast等的后面。如：
What are you talking about？
A paper on serfdom in Russian
In terms of natural resources
6.表示材料的介词
of和out of表示制成品的材料仍维持原材料的性质；with表示制成商品的一种成分；from表示制成品已失去了原材料的性质；in表示制成品的材料的色调或特殊性。
His house was built of brick.
She made these toys out of old cigar-boxes.
A fruitcake is made with fruit.
Steel is made from iron.
We have furniture of this design in oak and in walnut2.
