Runnable接口中的抽象方法是（）。
A、start
B、stop
C、yield
D、run
参考答案：D
— It's seven o'clock already.I must be leaving now.
— OK.________. [ ]
A. Go slowly
B. Stay longer
C. See you
D. Take it easy
—Could you tell me _____ for the meeting yesterday?
—Because the traffic was bad. [ ]
A. why did you come late
B. why you came late
C. why do you come late
D. why you come late
