介词作用

介词（Preposition）是用来表示名词、代词或短语与句子其他部分的关系的词。常见的关系包括方向、时间、地点、方式、原因、对象等。介词不能单独使用，通常与其后的名词或代词构成介词短语。

介词的分类及用法

1.方向和运动介词

这些介词表示移动的方向，常与动词（如go, come, move等）搭配使用。

介词 含义 例句
to 到…… She went to the office.
into 进入……（内部） He walked into the room.
onto 到……（表面） The cat jumped onto the table.
out of 从……出来 He got out of the car.
from 从…… They came from France.

2.位置和地点介词

表示物体或人所处的位置。

介词 含义 例句
in 在……里面 The keys are in the drawer.
on 在……上面 There is a book on the table.
at 在……（具体地点） I will meet you at the station.
under 在……下面 The shoes are under the bed.
between 在……之间 The school is between the park and the library.
behind 在……后面 The car is behind the house.

3.时间介词

表示事件发生的时间。

介词 含义 例句
in 在……（较长时间） We met in 2020. / She was born in July.
on 在……（具体日期） He arrived on Monday.
at 在……（具体时刻） The train leaves at 7 a.m.
since 自从…… They have lived here since 2015.
for 持续……时间 We stayed there for two weeks.
before 在……之前 Finish the work before lunch.
after 在……之后 He called me after the meeting.

4.方式和手段介词

表示做某事的方式或工具。

介词 含义 例句
by 通过…… We traveled by car.
with 用…… She wrote with a pen.
in 以……方式 He spoke in a loud voice.
on 通过……（通信方式） She talked to him on the phone.

5.原因、目的和伴随关系介词

表示原因、目的或与某人/某物在一起。

介词 含义 例句
because of 因为…… The match was canceled because of the rain.
due to 由于…… The flight was delayed due to bad weather.
for 为了…… This gift is for you.
with 与……一起 She came with her friend.

介词与其他词类的区别

介词 vs. 副词

介词后面通常接名词/代词，而副词则独立存在。
例：He went out of the room. (介词短语)
例：He went out quickly. (副词)

介词 vs. 连词

介词后接名词或代词，而连词连接两个句子。
例：I left because of the noise. (介词)
例：I left because it was too noisy. (连词)