These are fruit. This is vegetables. 对吗.为什么?

\u4e3a\u4ec0\u4e48\u770b\u89c1\u6709\u4e9b\u5730\u65b9Franch fries\u7528them\u800c\u4e0d\u7528them.\u8fd8\u6709\u5f53\u7528vegetables and fruit\u65f6\u7528are\u8fd8\u662fis

Franch fries \u662f\u590d\u6570\uff0cvegetables and fruit\u662f\u7528is\u8fd8\u662fare\u6839\u636e\u5c31\u8fd1\u539f\u5219\uff0c\u8c01\u5728\u540e\u5c31\u6839\u636e\u5355\u590d\u6570\u6765\u51b3\u5b9a\u7528is\u8fd8\u662fare\u3002

is \u770b\u505a\u4e00\u4e2a\u6574\u4f53

蔬菜水果不可数的
如果加S，表示各种蔬菜，各种水果
there are fruits 有几种水果
there is fruit 有一些水果

this is vegetable 有一些蔬菜
there are vegetables 有几种蔬菜

你的问题是后面加S了，be动词要不要对应单复数
是吗？
看看我的例子
清楚吗？

These are fruits .These are vegetables.

fruit vegetable都是复数名词

These are vegetables.

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