回复：急问：Ｆ１能否在其它学校校内工作单位２０小时／ＷＥＥＫ？

my understanding is that 20-hr job should be connected to your current institution. For example, I was in a joint phd program that required me to work at another college for 20 hrs, but the program was a joint one between my F1 sponsor and the other institution. In this case, it is ok. Otherwise, you have to use your OPT or CPT. good luck