给您的KDJ指标加两条线超卖，超买线：20和80；也就是在原代码上加上M3、M4这两行代码

RSV:=(CLOSE-LLV(LOW,N))/(HHV(HIGH,N)-LLV(LOW,N))*100;
K:SMA(RSV,M1,1);
D:SMA(K,M2,1);
J:3*K-2*D;

M3:20,LINETHICK1,COLORRED;

M4:80,LINETHICK1,COLORYELLOW;