aOn=new Image;aOn.src = "img/32[2].jpg";aOff=new Image;aOff.src = "img/32[1].jpg";
bOn=new Image;bOn.src = "img/34[2].jpg";bOff=new Image;bOff.src = "img/34[1].jpg";

function switchOn(imgName){
  imgOn = eval(imgName + "On.src");
  document [imgName].src=imgOn;
}

function switchOff(imgName){
  imgOff = eval(imgName + "Off.src");
  document [imgName].src = imgOff;
}