you become a professional soccer player, you will have a happy life.
A:If
B:Unless
C:Until
2016年8月5日—21日,第31届夏季奥运会将在巴西的里约热内卢举行。读图,巴西( )
—Have you ever _______ to bring your homework to school?
—Yes. I _______ it at home once last term.
下列有关原子的说法正确的是( )