dot't forget___the door and windows when you leave .(A,closing B,to close C,closed D,to closing)

dot't forget___the door and windows when you leave .(A,closing B,to close C,closed D,to closing)
dot't forget___the door and windows when you leave .(A,closing B,to close C,closed D,to closing)

dot't forget___the door and windows when you leave .(A,closing B,to close C,closed D,to closing)
B,to close
forget to do 忘记做没事……
区别于 forget doing sth 做过某事,但忘了（自己做过）

B to close
forget to do sth 表示别忘了要去做某事

to close