222. The gentleman made an apology for the mistake he had       , for he had taken my suitcase _____ mistake the day before.

A．had; for

B．made; for

C．had; by

D．made; by

控制拉伸点必须稳定（）。

A、初生纤维纤度

B、拉伸倍数

C、拉伸温度

D、拉伸速度