Parse error: syntax error, unexpected '}' [closed]

Answer 1

you have missed semicolon in this line:

redirect_to("new_subject.php");

try this:

 if (!empty($errors)) {
        $_SESSION["errors"] = $errors;
        redirect_to("new_subject.php");
    } 

Answer 2

Missing semicolon on the line above the brace.

redirect_to("new_subject.php")

A lot of times you have to look at the line above the one given in the error to see what the problem is.