Prueba así:
Código php:
Ver original$Sql="INSERT INTO 'usuarios'
(name, lastname, username, password, verifypasswsord, email, gender, city, zipcode, sport)
VALUES ('{$_POST['name']}', '{$_POST['lastname']}', '{$_POST['username']}', '{$_POST['password']}', '{$_POST['verifypassword']}', '{$_POST['email']}', '{$_POST['gender']}', '{$_POST['city']}', '{$_POST['zipcode']}', '{$_POST['sport']}')";