求教innerHTML怎么不覆盖

求教innerHTML如何不覆盖

JScript code

                  var cb=$("Layer8");                                                            for(i=1;i<=8;i++){                    cb.innerHTML=eval("colour"+i+".src");                                     cb.innerHTML=eval("colour"+i+".p1");                    cb.innerHTML=eval("colour"+i+".p2");                }                break;