蝗虫生活在干燥的环境中,防止水分散失的结构是 ( )
A:肺
B:气管
C:气囊
D:外骨骼
下列各项中,不属于类人猿的是( )
—Yes. I ______ it since I entered the college. This is a best-seller.
若|m-3|+(n+1)2=0,则2m-n的值是( )