Custom fields using My custom function leads to error

Hello

I am developed a site and I would like to add some custom fields in my form. I took the first part of the code from one example ( see below) using the plugin my custom function. But unfortunately it leads me to a error ( 500)
Can you please help me with that.

Thanks a lot in advance
Marcela

function give_myprefix_custom_form_fields( $form_id ) {
// Only display for forms with the IDs “754” and “578”;
// Remove “If” statement to display on all forms
// For a single form, use this instead:
// if ( $form_id == 754) {
$forms = array( 73, 488 ); ?>
<div id=”give-referral-wrap”>
<label class=”give-label” for=”give-referral”><?php _e( ‘How did you hear about GDI?:’, ‘give’ ); ?> <span class=”give-tooltip icon icon-question” data-tooltip=”<?php _e( ‘Please take a second to tell us how you first heard about Girl Develop It.’, ‘give’ ) ?>”></span>
</label>
<textarea class=”give-textarea” name=”give_referral” id=”give-referral”></textarea>
</div>
<?php endif;

}
add_action( ‘give_after_donation_levels’, ‘give_myprefix_custom_form_fields’, 10, 1 );