It took him a long time to ______ the skills he needed to become an artist.
According to the rules, students ______ get grades not lower than 85% in any subject in order to get the scholarship.
Student loan is supposed to provide financial support for people who would ______ not be able to go to college.
The young scientist has made such great achievements in his chosen field ______ nobody else can make.
We were told not to touch the equipment in the laboratory unless ________.
---Where did you first meet your boyfriend?---It was in the department store ______ he worked.