SQL confusing error [duplicate]

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• Reference - What does this error mean in PHP? 28 answers

include 'conn.php';

if($_POST) { $sql="UPDATE users SET $pass="mysql_real_escape_string($_POST['pass']). " $fname="mysql_real_escape_string($_POST['fname']). " $lname="mysql_real_escape_string($_POST['lname']). " $mi="mysql_real_escape_string($_POST['mi']). " $age="mysql_real_escape_string($_POST['age']). " $course="mysql_real_escape_string($_POST['course']). " $yearlevel="mysql_real_escape_string($_POST['yearlevel']). " WHERE id=" . mysql_real_escape_string($_POST['id']);

if(mysql_query($sql))
    {
        //this will be displayed when the query was successful
        echo "Record was edited.";
    }
else
    {
        die("SQL: " . $sql . " >> ERROR: " . mysql_error());
    }

}

I have this kind of very confusing error :

Parse error: syntax error, unexpected 'mysql_real_escape_string' (T_STRING) in C:\xampp\htdocs\beast\beast\edstul.php on line 15

It is very confusing for me.

What are the solution for this guys.