The U.S. has a surplus of science jobs but not enough college graduates to fill them. Studies find that 40 percent of students planning to major in science, technology, engineering or mathematics end up switching majors or don’t finish. To help change that, there's an initiative at Johns Hopkins to engage students in so-called “active learning" entry-level science courses. VOA's Rosanne Skirble reports.
v. 答应,预定,使忙碌,雇佣,订婚