There are two kinds of this four plus one. One is national defense students, that is, students trained by the army in local universities, who study in local universities for four years, then go to military schools for one year, and then assign jobs. The other is an officer specially recruited by the army from local college students. As for what to test, it depends on what major he recruits and what major you study. You can ask the local people's armed forces department about this, and the registration is also there.