Look!The man must ___catch the early bus.A.is runing to B.be runing to C.is runing
问题描述：
Look!The man must ___catch the early bus.A.is runing to B.be runing to C.is runing
D.be runing for
答
Look! The man must _B.be runing to __catch the early bus.为什么啊？must be 是固定搭配，be + 动词ing ， run to catch the bus 跑去赶公交车