单项选择题
Which of the following statements is true about the students in the Middle Ages （）
A．They took objective. B．They specialized in one subject. C．They were timed by electrical clocks. D．They usually took spoken tests.
单项选择题 21（）
填空题 A．matter B．happen C．marry D．wander
单项选择题 He doesn't know ______ or go home.
