Chinese athletes did a great job in 2012 London Olympics. It can encourage post-90s(90后) _______.
A:work harder
B:works harder
C:to work harder
D:to working harder
单词拼写。
珠江三角洲地区在与港澳地区的合作中,充当的主要角色是( )
与椭圆x24+y2=1共焦点且过点Q(2,1)的双曲线方程是( )
请回答: