韶山8型电力机车弹性拉杆由（）和拉杆组成。
A.橡胶垫
B.橡胶圈
C.圆弹簧
D.橡胶
参考答案：D
临时备用医嘱，从医生开始写时有效时间为（）。
A.22h
B.20h
C.18h
D.14h
E.12h
—Is ______ your dictionary?
—Yes, thank you. And ______ are my books. [ ]
A. this; this
B. this; these
C. these; this
D. these; these
