collaborate

你不是和他合作过你的一本书吗？

Didn't you ___collaborate with him on one of your books?

要解决复杂的全球性问题，各国必须合作并汇集专业知识。

To solve complex global issues, nations must ___collaborate and pool their expertise.

为解决复杂的全球性问题，科学家们必须跨学科、跨国界进行合作。

To solve complex global issues, scientists must ___collaborate across disciplines and borders.