介词一般与介词宾语连用,介词宾语必须是名词或名词性结构.拿介词 in 来举例：in the room,in our country,in place,in time,in the tree,in my way,in a beautiful dress,in hospital,in the army,in my bag,in 1990's,in 2011,in this week,in July,in trouble,in dismay.介词组成的短语可以与主语和系动词连用,构成主系表结构的句子.还可以做定语、状语与名词和动词连用.
