function play3(i) {

    if (i == 1) {
        audio.currectTime = 0;
        audio.play();
        i = i + 1;
        setTimeout("play3(2)", 2000);
    } else if (i == 2) {
        audio.currectTime = 0;
        audio.play();
        i = i + 1;
        setTimeout("play3(3)", 2000);
    } else if (i == 3) {
        audio.currectTime = 0;
        audio.play();
        i = i + 1;
        setTimeout("play3(4)", 2000);
    } else if (i == 4) {
        audio.currectTime = 0;
        audio.play();
        i = i + 1;
    }

}

function play3(i) {
    audio.currentTime = 0;
    audio.play();
    if (i == 1 || i == 2 || i == 3) setTimeout("play(" + (i + 1) + ")", 2000);
    i += 1;
}

------解决方案--------------------
function play3(i) {
	audio.currectTime = 0;
	audio.play();
	i = i + 1;
	if(i != 5){
		setTimeout("play3("+i+")", 2000);
	}
}

这个意思？