他们；她们；它们people, animals or things that have already been mentioned or are easily identified
‘Where are John and Liz?’ ‘They went for a walk.’
They(= the things you are carrying) go on the bottom shelf.
（用以代替 he 或 she，指性别不详的人）used instead ofhe orshe to refer to a person whose sex is not mentioned or not known
If anyone arrives late they'll have to wait outside.
（泛指）人们，人人，众人people in general
The rest, as they say, is history.
权威人士；上面（指负责人）；专家people in authority or experts
They cut my water off.
They now say that red wine is good for you.