When you leave the room, don't forget to keep the door ________.

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When you leave the room, don't forget to keep the door ________.

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“Please don't forget ______ the door when you leave.”     “No, I won't forget ______ it.”

---“Please don’t forget ______ the door when you leave.”     

---“No, I won’t forget ______ it.”

1. A.
   to lock; to lock
2. B.
   to lock; locking
3. C.
   locking; to lock
4. D.
   locking; locking

 “Please don't forget ______ the door when you leave.”     “No, I won't forget ______ it.”

  A. to lock; to lock   B. to lock; locking         C. locking; to lock         D. locking; locking