Jiahululu is right.

谢谢你的回答,但是没看懂你说的,我为什么还要回国再签证?我也有I797A TD转H4的PAPER啊.
-Your H4 approval notice is only valid within U.S. When you leave U.S., this H4 appoval notice becomes useless. So, you need to get an H4 visa to come back based on your spouse's H1 approval notice. Then, you will get a H4 I-94 at the port of entry when you enter US with the H4 visa. Your this new I-94 duration should be the same as your spouse's H1. So, check your I-94 duration when you enter US. if it is not the same duration as your spouse's H1, ask the CBP officer to fix it for you at the port of entry immediately.