join 和 join in 用于参加活动时有什么区别

用 joined, joined in 填空：

Soon some of the teachers ______ the singing.

Some of usdecided to _____ the strike.

Everyonethere ______ the conversation.

除写出答案，也请老师剖析一下缘由。

用 joined, joined in 填空：

Soon some of the teachers ______ the singing.

Some of usdecided to _____ the strike.

Everyonethere ______ the conversation.

【答】《薄冰英语惯使用方法词典》指出：join 意思是“加入（某项活动），可与 in 连用。...... We shall be glad to join the discussion . 大家将非常高兴参加这项讨论。

所以，这几道题填joined 或者 joined in 都正确。