图5-51所示两跨等截面梁，受移动荷载P作用，截面相同，为使梁充分发挥强度，尺寸a应为（）。
A.A
B.B
C.C
D.D
参考答案：B
— What's your friend like?
— _____. [ ]
A. He is English.
B. He's a teacher.
C. He is tall and thin.
D. He likes sports.
顶梁与顶板间应怎样处理？
