俗话说“秀才不出门,能知天下事”这句话由老子的哪句话演变而来:()
A、不出户,知天下
B、不窥牖知天道
C、智慧出,有大伪
D、居善地,心善渊
参考答案:A
-__________ has your friend been to the Great Wall?
-Twice.[ ]
A. How often
B. What time
C. How long
D. How many times
列车在下坡启动时司机应如何操作?