So let's look at the book again. Sentence number two, "are you sure that we've never met before?"

我们再来看书，第二个句子，“你确定我们以前没见过面吗？”

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The subject of a sentence and its verb must agree in number.

句子的主语和动词的数必须一致。

《牛津词典》

Paragraph 4 mainly tells us the number of sentence structures of human languages.

第四段主要讲述人类语言中句子结构的数量。

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"The jury verdict form does not indicate the number of jurors who voted for a sentence of life or the number of jurors, if any, who voted for a sentence of death, " Adams said.

CNN: Moussaoui jury split on mitigating factors

Under the extended part of the sentence, a number of conditions can be attached before Wemyss is released on licence.

BBC: Robert Wemyss

Still, we pry, and usually end up tussling with our subjects over a sentence here and a number there.

FORBES: Blindsided by Booms