There is an apple,two bananas and some oranges on the plates

主语是:an apple,two bananas and some oranges
There be 句型是一个约定俗成的倒装句(倒装已成习惯用法).
这里"there"是引词无词义
谓语(be动词)
主语:an apple,two bananas and some oranges
状语:on the plates
原句还原成陈述句如下:
An apple,two bananas and some oranges are on the plates.
可以看出同样是表达某物在某处,但陈述句远不及There be 这种约定俗成的倒装结构给人的那种形象而又生动的感觉.
补充:There be 结构中的谓语动词,采用就近原则
如:There "is" an apple,two bananas .
There "are" two bananas ,an apple.
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