条痕
参考答案：矿物在无釉的白色瓷板上磨划时留下的粉状颜色。
— He didn't win the race at last, did he?
— _________, though he tried to run as fast as he could. [ ]
A. No, he didn't
B. Yes, he did
C. No, he did
D. Yes, he didn't
压力容器的密封方式主要有强制密封、自紧密封。（）
