"我们需要合作。"

Translation: We need to collaborate.

[AussieCrisp]

We must cooperate. I think that should be accepted.

[chris789463]

'Work together' feels more idiomatic to me

[wbeeman]

"We must collaborate" is correct but not accepted. Please correct.

[Hanrong5]

Why not "we need colloberatio"?

[Melody423394]

Maybe because of spelling error. Should be "collaborate". Maybe also because Duo prefers verb (collaborate), not verbal noun (collaboration, which was also misspelled).

[Hanrong5]

Colloberation

[Melody423394]

I looked up 合作 and found that it. can mean to cooperate, to collaborate, to work together, or cooperation. See https://www.wordhippo.com/what-is/the-meaning-of/chinese-word-27df72658dd3dba423507cc868c25bec5b5a5f55.html and https://mandarintemple.com/dictionary/chinese-to-english/hsk-5/%E5%90%88%E4%BD%9C-he2-zuo4/.