join in多指參加某組織，成為其中的一個成員，指參加到某些人當中去做某事，這項活動往往正在進行著；take part in指參加會議或者群眾性的活動等，重在說明句子的主語參加該項活動并在活動中發揮作用。

take part in例句

The officer refused to let his men take part in the operation.

這軍官拒絕讓他的士兵參加這項軍事行動。

Six theatre companies have been selected to take part in this year's festival.

You don't need strength to take part in this sport

參加這項運動不需要太多體力。

They returned to take part in the season's opening game.

他們回來參加本賽季的開幕賽。

You can take part in activities from canoeing to bird watching.

你可以參與從劃獨木舟到觀鳥等各種活動。

join in例句

I hope that everyone will be able to join in the fun

我希望每個人都能夠加入進來，玩得開心。

You still have time to join in the fun.

現在加入其中享受快樂還來得及。

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

我們玩電子游戲時，他偶爾會和我們一起玩。

No matter how often they were urged, they could not bring themselves to join in

就算別人說破了嘴皮，他們就是不加入。

The main rebel groups have agreed to join in a meeting to set up a transitional government.

主要叛亂集團已同意參加會議討論建立一個過渡政府。