[jiā rù]
（加上） add; mix; put in
[動]
（參加） join;accede to;take part in
join in the stream of people
加入人流
accede to a treaty
加入條約
join the Communist Party
加入共產黨
All of us joined lustily in the chorus.
我們全都勁頭十足地加入了合唱。
As the guide was showing us round the museum, two or three foreign tourists joined themselves on to our party.
導游領著我們參觀博物館時， 有兩三個外國游客也加入了我們的行列。
I'll take part in everything good you do.
我將采取一切你做的好的部分。