句型转换（5%，每线0.5）

小题1:“When will he have a concert?” the boy asked.（改为间接引语）

The boy asked       he         have a concert

小题2:These tigers are facing great danger.（改为感叹句）

_________  ________ danger these tigers are facing!

小题3:Was he killed? Did he kill himself? I wonder. (合并为一句)

I wonder _________ he was killed _________ he killed himself.

小题4:We shall make an extra model.（改为同义句）

We shall make __________  ___________ model.

小题5:To prevent us from floating in the air, we must wear special boots.(提问)

_________  _________ we wear special boots?

重量为100N的木箱放在水平地板上，至少要用40N的水平推力，才能使它从原地开始运动．木箱从原地移动以后，用38N的水平推力，就可以使木箱继续做匀速运动．由此可知：木箱与地板间的最大静摩擦力为______N，它们间的动摩擦因素等于______．在运动过程中如果改用20N的水平推力推木箱时，摩擦力等于______N．