根据句意及首字母提示补全单词。

小题1:Think it over before you make an important d___________.

小题2:Stupid is another way of saying s_____.

小题3:Our teachers taught us to sing l____ songs before class.

小题4:My parents often tell me not to speak to s_______

小题5:Yesterday he f________ in the exam, so his father hit him.

数控机床的冷却液开关在（）位置时，是手动控制冷却液的开关。

A、SPINDLE

B、OFF

C、COOLANT ON

D、M CODE