单项选择题
A.centuries B.too long C.some time D.many years
A. stand up and offer her his seat B. read his newspaper C. look out of the window D. not stand up and offer her his seat
A. Taller trucks can pass under them. B. Pedestrians can climb up and have a view of the city. C. They are safer for pedestrians and can keep traffic moving at the same time. D. They are easier and more convenient for the pedestrians.