机动车在高速公路上发生故障时，警告标志应当设置在故障车来车方向多少米以外？
参考答案：150米
The Smiths _____ their breakfast when the morning post came. [ ]
a. had
b. has been having
c. are having
d. were having
翻译下列句子。
①征于色，发于声，而后喻。
______________________________________________
②空乏其身。
③然后知生于忧患，而死于安乐也。
