什么叫完全燃烧？
参考答案：
燃料中的可燃物质和氧进行了充分的燃烧反应，生成的燃烧产物中已不存在可燃物质，这种燃烧称为完全燃烧。
Last night Mr. Crook didn’t come back at the usual time. ______, he met some friends and Stayed out until midnight.
A．Meanwhile
B．However
C．Instead
D．Yet
大脑皮质听区在（）
A.颞横回
B.角回
C.缘上回
D.距状沟两侧
E.颞上回
Last night Mr. Crook didn’t come back at the usual time. ______, he met some friends and Stayed out until midnight.