sit up 1. (使)坐起来；坐直 Sit up, children! Don't lean over the table! 坐直，孩子们!不要趴在桌子上! 2. 不睡，熬夜 Don't sit up for me if I'm late. 我如回家迟，你就先睡，不要等我。 3. 〈口〉警觉；诧异；关注 She really sat up when I told her the gossip about Tom. 我把有关汤姆的闲话告诉她时，她确实大吃一惊。 Devaluation of the dollar made the financial market sit up. 美元贬值引起金融市场的关注。