14.While _____ the food with the microwave oven,I heard someone ______ at the door.A.heated; knocking B.heating; knocking C.heat; knocking D.be heated; knocks
问题描述：
14.While _____ the food with the microwave oven,I heard someone ______ at the door.
A.heated; knocking B.heating; knocking
C.heat; knocking D.be heated; knocks
答