Native speakers can distinguish between grammatical and ungrammatical sentences even when they have never heard particular combinations before.

母语使用者可以分辨符合语法规则和不符合语法规则的句子，即使他们以前从没有听过这些特定的词语组合。

《柯林斯英汉双解大词典》

Grammatical sentences are formed following a set of syntactic rules.

句法是一个规则系统。

youdao

So, if you want to estimate how many grammatical sentences under twenty words in English, the answer is, "a lot."

如果你想估计一下，用二十个英文单词，可以组成多少个符合语法的句子，答案会是，“很多”。

youdao

So, if you want to estimate how many grammatical sentences under twenty words in English, the answer is, "A lot."

如果你想估计一下,用二十个英文单词,可以组成多少个符合语法的句子,答案会是,"很多"

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