---Dad, must we wait until the light becomes green?---Yes, I’m afraid we ______. That’s the traffic rule.

(2013·安徽师大附中高三七模)Don't use water to put out the fire if oil catches fire. As is known, oil ________ float on water.

—Do you want to play basketball after school, Jack?—   . I have to practice my English.

The weather in Inner Mongolia is always dry, but sometimes it _____ rain heavily. 

Some young people these days just ________ go out of their homes to contact the real world．