close the windows before you leave the classroom.为什么这个句子判定为祈

Close the windows before you leave the classroom.为何Close用原型, ___the windows before you leave the classroom. Be s＿ to close the windows before you leave the classroom ---------(close)the windows before you leave the classrom. ------the windows before you leave the classroom.(please),谢了 Be ----to close the windows before you leave. Before you leave the classroom,please r____to close the wind I____(close)the windows before I leave. Don't forget to close all the windows before you leave the c Students__________ to close the windows before they leave th R____ to close the windows when you leave. Remember ______(shut) all the windows before you leave