— Can you play ________ guitar?
— Sure. It's a piece of cake for me.
A:a
B:an
C:the
D:/
下列各句中,没有语病的一项是 ( )
He said he would help me with my maths if he ____ free.
如图,是某日太阳光照图,读图回答:
这一天,北半球的节气应是( )