接触面上滑动区的摩擦条件是库伦摩擦。
A. 对
B. 错
It _____ a time when they had some control over their fate.[音频]（来源：NPR News）
A. makes them feel guilty for
B. makes them think of
And we want every citizen to _____ this land that we all love so much.[音频]（来源：欧美名人演讲）
A. feel ashamed about
B. take pride in
Inexperienced Tippi Hedrens can be made to _____.[音频]（来源：经济学人）
A. embark
B. embarrass
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