<html><head><script type="text/javascript">function gettip(txt){document.getElementById('tip').innerHTML=txt}function reset(){document.getElementById('tip').innerHTML=""}</script></head><body><p>把鼠标移动到下面的饮料上：</p><span onmouseover="gettip('热的黑色饮品')"onmouseout="reset()">咖啡</span><br /><br /><span onmouseover="gettip('冷的白色饮品')"onmouseout="reset()">牛奶</span><p id="tip"></p></body></html>