图为某岛屿地形示意图,下列说法正确的是( )
下列各组函数中,表示同一个函数的有____
①y=x2-1x-1与y=x+1; ②y=x与y=|x|;
③y=|x|与y=x2; ④y=x2-1与y=x﹣1.
With the quality-oriented education (素质教育) being carried out, teachers won't too much importance to students' grades.