合作是取得成功的关键。

Hézuò shì qǔdé chénggōng de guānjiàn.

Cooperation is the key to success.

他们之间没有合作精神。

Tāmen zhī jiān méiyǒu hézuò jīngshén.

There is no spirit of cooperation between them.

我们需要合作解决这个问题。

Wǒmen xūyào hézuò jiějué zhège wèntí.

We need to cooperate to solve this problem.