英语的词汇辩析

说"加入(党派,社会,团体等)"用join,不可用join in,例如:He joined the Pupil's Association last year.
说"加入(某种活动)"用join或join in都可以,如Will you join (in) the game?和We shall be glad to join (in) the discussion.
说"加入(某种活动)"而那"活动"用动名词表达,用join in,不可用join,如:I joined in rowing.

参考书目:<英语惯用法词典>