题目

如图,将∠BAC沿DE向∠BAC内折叠,使AD与A’D重合,A’E与AE重合,若∠A=300,则∠1+∠2=（ ） 500      B．600         C．450       D．以上都不对 答案：B  All of us were _____ by the _____ questions _____ by a six-year-old boy.  A. puzzled; puzzling; rose              B. puzzling; puzzled, raised  C. puzzling; puzzling; risen            D. puzzled; puzzling; raised