It's hot. What about________ the door?
open
to open
opening
What about+doing sth 表建议。
Please _____ the TV. It's time to go to bed.
turn on
turn off
put on
put off
turn on 意为“打开，接通”；turn off 意为“关掉；切断”；put on 意为“穿上；增重”；put off 意为“推迟”。由下文“It's time to go to bed.（该上床睡觉了）”可知，空格所在句意为“请关掉电视”。