题目

This is _________ my father has taught me—to always face difficulties and hope for the best. A . how B . which C . that D . what 答案：D（2004•盐城）解分式方程时，可设=y，则原方程可化为整式方程是（ ）A．y2+2y+1=0B．y2+2y-1=0C．y2-2y+1=0D．y2-2y-1=0