国际市场营销的约束力是（）
A.新技术革命的推动
B.杠杆作用
C.市场差异
D.国内竞争的压力
参考答案：C
Do remember to __________the lights before you leave. If you leave them _______, the boss will be
angry with you. [ ]
A. turn on, on
B. turn down, off
C. turn off, off
D. turn off, on
小儿肺炎鉴别诊断
