beforehand

I wish you had told me about the change in plans beforehand so I could prepare.

(Chinese) 我希望你预先告诉我计划的变动，这样我也能准备一下。

The catering staff arrived two hours beforehand to set up the tables for the wedding.

(Chinese) 餐饮工作人员提前两小时到达，为婚礼摆放桌椅。