当牵伸倍数超过3倍时，牵伸倍数越大，牵伸力越大，伸直前弯钩纤维效果越好而伸直后弯钩纤维的效果越差。
参考答案：错
— Can you come to my birthday party tonight?
— I’d love to, but I______ on a patient at 6 o’clock.
A．will operate
B．am operating
C．will be operating
D．will have operated
震前地下水有哪些异常变化？
