单项选择题
M: You are going to Washington tomorrow, aren’t you W: Yes. I thought I’d fly, but then I decided that taking a bus would be cheaper than driving or flying.
A.By plane. B.By bus. C.By car.
A.430 B.300 C.330 D.100
A.be reasonably doubtful about them B.check all their answers C.substitute them for basic thinking D.use them for business purposes only