join the后加什么

　　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。