join后一般接某项活动。

例如：

I hope everyone will join in the fun.我希望每个人都能参与这个娱乐活动。

join in作 参加，加入讲时，一般指参加某项活动，join作 参加，加入 讲时，一般指参加某一组织、团体或某群人。

扩展资料

He started to sing and I joined in.

他开始唱起歌来，然后我也跟着唱起来。

You don't have to join in; there are more than enough people on the job already.

人够多了，您就不用插手了。

Now and again he'd join in when we were playing video games.

我们玩电子游戏时，他偶尔会和我们一起玩。

I didn't want to join in, but Kenneth insisted.

我不想加入，但是肯尼思非要坚持。

I did my best to join in, but the conversation was largely unintelligible.

我努力想插上话，可是大部分谈话内容我都听不懂。