我们最终到达了山顶 We got to___ ___ ___ ____ ____in the en

We got to  the  top   of   the   mountain    in the end. 

I often take  part   in    all kings of after-class activities. 

take part in表示参加，而play a part in则表示在某个里面演一个角色或起某个作用。

Britain should play its full part in the negotiations. 英国应全力参与这些谈判。

have a part to play in 的意思是“在……中发挥作用”

The church used to have a more important part to play in the community. 教会曾经在社区中发挥过更大的作用。

play a part in 也常常含有“在……起作用”的意思，因为参与其中自然就要发挥作用。

Pictures play an important part in publishing. 图片在出版业中起到重要作用。

She played a major part in the success of the scheme. 她对该计划的成功起了重要作用。

The iron and steel industry plays an important part in our national economy. 钢铁工业在国民经济中起重要作用。