18．On October 31st, known as Halloween, dozens of children costumes knock at their neighbor’s doors and yell “Trick or Treat” when the door .
A. putting on; is open
B. dressed up in; opens
C. having on; is open
D. wearing on; open
网友回答
A. putting on; is open
(答案→)B. dressed up in; opens
C. having on; is open
D. wearing on; open
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