在They live in the country一句中，动词复数形式live与复数主语they一致。

In the sentence 'They live in the country', the plural form of the verb 'live' is in agreement with the plural subject 'they'.

《牛津词典》

在Tom likes jazz一句中，动词单数形式likes与主语Tom一致。

In 'Tom likes jazz', the singular verb 'likes' agrees with the subject 'Tom'.

《牛津词典》

动词的数和人称与主语一致。

The verb agrees with its subject in number and person.

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