— Do you often play _____ piano?
— Yes. I want to be _____ musician like Lang Lang.
A:the; a
B:a; the
C:the; an
计算:(10)2=____ .
推论:如果木块在水平面受到的阻力为零,木块将____ .
有关光合作用和呼吸作用说法不正确的是( )