Nonverbal messages can be used to accent or emphasize distinct points in verbal messages. Which of the following are the examples of accenting

A． Saying something quicker than usual.

B．Pausing before saying something.

C． Saying something in a lower voice than usual.

D．Saying something louder than usual.

錾子的前刀面是切削部分与（）接触的表面。

A.工件表面

B.切削表面

C.切屑表面

D.未加工面