我国南北向铁路大动脉是( )
Though he is at home, he doesn't feel for he has many things to do.
下列属于有性生殖的是( )
①以经济建设为中心,大力发展生产力
②坚持区域经济协调发展,消除地区差异
③坚持走中国特色社会主义道路
④坚持同步富裕原则,共享改革发展成果
-5的相反数是( )