---I can't work out the math problem, what should I do?
---You can turn to the teacher.
造成下图中两个变量走势相异的最可能的原因是,2007~2015年我国( )
—Who helped you with your English?
—_______! I learned it all by myself.
关于人类对海洋的科学探索,下列说法正确的是( )