.half {
*zoom: expression( this.runtimeStyle['zoom'] = '1', this.innerHTML = ' ');
}
.full {
*zoom: expression( this.runtimeStyle['zoom'] = '1', this.innerHTML = ' ');
}
.half:before { content: '2002'; speak: none; }
.full:before { content: '2003'; speak: none; }
<ul>
<li class="li">姓<span class="full"></span><span class="full"></span>名:<input type="text" /></li>
<li class="li">手<span class="half"></span>机<span class="half"></span>号:<input type="text" /></li>
<li class="li">电子邮箱:<input type="text" /></li>
</ul>