they单数形式是it，he，she。they的意思是他们，她们，它们，用以代替he或she，指性别不详的人，（泛指）人们，人人，众人。they的例句：They won by a single goal after extra time（他们在加时赛中仅踢进一球即获胜）。

they的例句：Cars are checked as they come off the production line（汽车下了生产线立即进行校验）；It's a mistake they almost always make（这是他们几乎总要犯的错误）。