"sit back and let happen" in Chinese (Simplified)
袖手旁观
Definition
不采取行动，只是让事情自然发生，即使你本可以有所作为。
Usage Notes (Chinese (Simplified))
这个表达常带有批评或不赞成的语气，暗示某人本应采取行动却选择袖手旁观。常用于讨论责任或错失良机时。语境不同，语气也会不一样。
Examples
Sometimes you can't just sit back and let happen when you see a problem.
有时候看到问题时，不能只是**袖手旁观**。
She didn't want to sit back and let happen while her friends argued.
她不想在朋友争吵时只是**袖手旁观**。
We can't sit back and let happen if someone needs our help.
如果有人需要帮助， 我们不能**袖手旁观**。
He chose to sit back and let happen instead of getting involved in the situation.
他选择了**袖手旁观**，没有介入情况。
It's easy to sit back and let happen, but sometimes you have to take action.
**袖手旁观**很容易，但有时必须采取行动。
If you just sit back and let happen, things might get worse.
如果你只是**袖手旁观**，情况可能会变得更糟。