介词是一种虚词，它在句中的作用却非常重要。它用来表明名词与句中其他词的关系，不能单独使用。常考点包括一些固定搭配和一些近义词。下面是小编给大家带来的初中英语语法总结之介词解析，希望能够帮助到大家!
常用介词解析及用法比较：
at,on和in：这三个介词在试卷中的出现频率极高。对于它们的的分辨只要记住一句话就可以了。at表示点，on表示线，in表示面。什么意思呢?也就是说它们表达的范围逐渐增大。at six o'clock, at noon, at the age of sixteen等用at表示时刻或时间的点以及年龄。on具体到一周中的各天,日期及某特定的一天早上,下午,晚上：on Saturday，on July 1st，on my birthday，on the morning of July 16th，on a spring afternoon。in表达的范围更大一些。与世纪、年代、季节、月份以及早上、上午、晚上等连用。如：in the seventh century，in 1950's ,in 2000, in the morning等。
for,since：for表示多长时间。since后接时间起点,其终点往往为现在，常与完成时连用。牢牢记住哟。
after, in ：这两个介词都可以表示时间"在以后"的意思。其区别是：after 以过去为起点，表示过去一段时间之后，常用于过去时态的句子;in 以现在为起点，表示将来一段时间以后，常用于将来时态的句子。
by，with，in：by表示"以...的方式，方法，手段" 和 "乘某种交通工具";with指"借助于具体的手段或工具";in 表示"以......方式，用语言，文字等媒介"。
for和of：试比较：It's impossible for me to watch TV after eleven o'clock. It's kind of you to help me.
两句中介词的选择依据其前形容词而定,一般来说,of之前的形容词往往是用于描写人的品质的好坏，人自身的特点，如聪明与否，细心与粗心等;for之前的形容词用于描写事物的特点，如可能性，必然性，难易程度等。
好，又到了趁热打铁的时间了，来检测一下你的学习成效如何?
练习：
1. Can you tell the story ______Russian?
A. with
B. in
C. on
D. by
2. Here are some birthday cards ______ our teachers, ______ our best wishes.
A. of, with
B. for, with
C. of, in
D. for, in
3. The visitors _______Japan arrived _____ Beijing station last Tuesday morning .
A. from, at
B. of , to
C. from , to
D. of, on
4. He's badly hurt, we must send _____ a doctor at once.
A. to
B. up
C. on
D. for
5. Do you usually come to school ______ foot or _____- bike?
A. by ... by
B. on... on
C. on ... by
D. by ... on
6. --when was Jim born?
--______July, 18,1978.
A.on
B.at
C. in
D.to
7. WeiFang bought a new pen at a shop _____ her way home.
A. on
B. at
C. in
D. to
8. Don't tell anybody about it. Keep it a secret _______ you and me.
A. among
B. between
C. in
D. with
9. The teacher will be back ______ an hour.
A. in
B. after
C. of
D. at
10. -- How long have you been in Beijing ?
--I've been here _____ 1989.
A. in
B.since
C.on
D.for
实战：
1. ______man in brown is _____friend of my fathere's .
A. The.. the
B. The ... a
C. A... a
D. A... the
2. Here is a letter ______ you. It's ______your aunt.
A. to... for
B. for... to
C. from ... to
D. for ... from
3. The twins are ____ interested in Chinese food.
A. all
B. both
C. neither
D. each
4. It is ______ hot in Nanjing in summer.
A. too much
B. much too
C. much more
D. so much
5.That's too dear. Have you got_______?
A. cheaper something
B. everything cheaper
C. cheaper anything
D. anything cheaper
6. --Can I go out to play football now?
--No, you _______. You must do your homework first.
A. won't
B. can't
C. needn't
D. don't
7. The boy didn't go to bed _______ he was asked to.
A. while
B. since
C. until
D. as soon as
8. Lesson Two is ______ than Lesson One .
A. much difficult
B. much more difficult
C. the most difficult
D. little difficult
9. You'd better _______ here any longer.
A. don't stay
B. not to stay
C. to not stay
D. not stay
10. It _______ him half an hour to ride a bike to get here.
A. spent
B. used
C. took
D. paid
11. Mrs Read doesn't know ______ for her daughter.
A. what will she buy
B. which will she buy
C. to buy what
D. what she will buy
12. These childern have never seen snow, _______they?
A. do
B. don't
C. haven't
D. have
13. Why _______ shopping at once?
A. don't go
B. not go to
C. didin't go
D. not go
14. The Great Wall ______ all over the world .
A. is being known
B. was known
C. has known
D. is known
15. My friend has worked in that hospital_________.
A. since it opened
B. for it opened
C. since it opens
D. since it is open