Gravity form clone select instance

if(rgar($field,"cssClass") == "multi-choice"){
    $string = "<label class='gfield_label'>".__( 'Choose a teacher', 'my_theme' )."</label>";
    $string .= "<ul class='multi-select'>";

    $field_labels = array(1 => __( '1. choice', 'my_theme' ), 2 => __( '2. choice', 'my_theme' ),3 => __( '3. choice', 'my_theme' ));
    for($i=1;$i<=3;$i++){
        $string .= "<li>";
        $field_string = preg_replace("/(input_\\d{1,2}_\\d{1,2})/is", "$1_$i", $content); //Adjust field and label ID
        $field_string = preg_replace("/(<label[^>]+\>)(.*)(<\/label>)/s", "\$1"." ".$field_labels[$i]."$3", $field_string); //Replace each label
        $string .= $field_string;
        $string .= "</li>";
    }
    $string .= "</ul>";
    $content = $string;
}