错误 = 跨度>;
if（isset（

error = ""; if(isset(

_POST [' submit']）） // 此行表示如果按下提交按钮，请执行以下代码。
{

_POST['submit'])) //this line means that if the submit button is pressed do the following code. {

email = mysqli_real_escape_string（

email = mysqli_real_escape_string(