Don’t leave the water while you brush your teeth.A. runB. runningC. being runD. to run

问题补充：

Don’t leave the water while you brush your teeth.

A. run

B. running

C. being run

D. to run

答案：

A. run

(答案→)B. running

C. being run

D. to run

解析：考查固定搭配。Leave sb doing让某人一直不停地做某事；leave使…处于某种状态；句意：当你在刷牙的时候，不要一直让水流着。故B正确。