职称英语指导:语法知识——介词的意义a
介词是一种结构词,不能单独担任句子成分。介词的作用是表示它后面的宾语同句中其它词语之间的关系。介词与它的宾语构成介词短语可以充当多种句子成分。如:
The cost of food is rising. (定语)
She was ill during the meeting. (状语)
I found him in very good shape. (宾语补足语)
通常介词可分为四类:
简单介词:at, in, from, on;
复合介词:upon, inside, outside;
双重介词:from behind, from among;
短语介词:in case of, according to.
介词的意义
1.表示时间的介词
in表示“在某一时间段”,或“在……某一时候”,如用在月、季、年份、时代、世纪等时间名词的前面,或用来泛指一天的某一段时间。
in July / summer / 2000 / ancient times / the 1999‘s
in the morning / afternoon / evening
in也可以指“在……之后”,表示从说话起的若干时间内,如:
The bus will be here in ten minutes.
on表示“在特定的某一天”,也可用于带有修饰语的一天的某个时间段之前。如:on Saturday, on Saturday morning, on the morning of August 1st
at表示“在某一时间点”,或用来表示不确定的时间和短期的假日、时节等。如:
at six o‘clock, at Easter
介词over, through(out)两者均指“经过的全部时间”。
Stay over the Christmas.
介词for, since for表示动作或状态延续的全部时间长度,为“长达……”之意;since用于指从过去特定的某个时刻到说话时为止的一段时间;两者往往用于完成时。
I have been there for six years.
We have not seen each other since 1993.
during指“在……时期/时间内”,必须以表示一段时间的词或词组作宾语。
She was ill for a week, and during that week she ate little.