直到大学英文

I didn't realize until the university period and attention to the seriousness of the problem. Since then I started to record every section of the course content, collect and filter all the experience and method of effective targeted.

因为原句中用的是did和graduated,两个动词的过去式,表示这件事情发生在过去,而意识到真正想去做的事情也是说的当时想做,所以是wanted

He wasn't aware of the lost opportunities until graduation.

didn't 和be 不能在一起使用He wasn't aware of his wasting a lot of apportunities until graduating from college.

in college or univeristy