There is a “ No smoking “ sign here. You _________ smoke.

It’s cold here. _________ I switch on the heating?

(2013·潍坊市高三二模)Sometimes smiles ________ be false, hiding other feelings like anger, fear or worry.

(2013·高考四川卷)—Why are your eyes so red? You________have slept well last night.—Yeah，I stayed up late writing a report.

—Mr. Wang, must I come again to clean the window on Sunday morning?—No, you _____ . I have asked others to do it.