题目

 You'd better take something to read when you go to see the doctor ____ you have to wait. A.even if     B. in case         C. as if                D. in order that 答案：B把分式2xx+y中的x、y都扩大为两倍，那么分式的值（　　）A．扩大两倍B．不变C．缩小两倍D．不能确定