document.write("输入运算后得到的结果");
document.write("<table  border='0' cellspacing='0' cellpadding='2'>");
document.write("<tr>");
document.write("<td><input type='text' name='check_submit_nb' size='8'></td>");
document.write("<td><b><font color=#ffffff style='background:#000000;border:red 2px solid'>　9+<span id='check_chnumstr'>9</span>+<span>10</span>=?　</font></b></td>");
document.write("</tr>");
document.write("</table>");
document.writeln("<script language=\"JavaScript\">");
document.writeln("check_chnumstr.innerHTML=\"18\";");
document.writeln("<\/script>");
document.writeln("")