Add comments placeholder in WooСommerce

function my_product_review_comment_form_args( $comment_form ){

    $commenter = wp_get_current_commenter();

    $name_email_required = (bool) get_option( 'require_name_email', 1 );
    $fields              = array(
        'author' => array(
            'label'         => __( 'Name', 'woocommerce' ),
            'type'          => 'text',
            'value'         => $commenter['comment_author'],
            'required'      => $name_email_required,
            'placeholder'   => __( 'Name', 'woocommerce' )
        ),
        'email'  => array(
            'label'         => __( 'Email', 'woocommerce' ),
            'type'          => 'email',
            'value'         => $commenter['comment_author_email'],
            'required'      => $name_email_required,
            'placeholder'   => __( 'Email', 'woocommerce' ),
        ),
    );

    $comment_form['fields'] = array();

    foreach ( $fields as $key => $field ) {
        $field_html  = '<p class="comment-form-' . esc_attr( $key ) . '">';
        $field_html .= '<label for="' . esc_attr( $key ) . '">' . esc_html( $field['label'] );

        if ( $field['required'] ) {
            $field_html .= '&nbsp;<span class="required">*</span>';
        }

        $field_html .= '</label><input id="' . esc_attr( $key ) . '" name="' . esc_attr( $key ) . '" type="' . esc_attr( $field['type'] ) . '" value="' . esc_attr( $field['value'] ) . '" size="30" ' . ( $field['required'] ? 'required' : '' ) . ' placeholder="' . $field['placeholder'] . '" /></p>';


        $comment_form['fields'][ $key ] = $field_html;
    }

    $account_page_url = wc_get_page_permalink( 'myaccount' );
    if ( $account_page_url ) {
        $comment_form['must_log_in'] = '<p class="must-log-in">' . sprintf( esc_html__( 'You must be %1$slogged in%2$s to post a review.', 'woocommerce' ), '<a href="' . esc_url( $account_page_url ) . '">', '</a>' ) . '</p>';
    }


    if ( wc_review_ratings_enabled() ) {
        $comment_form['comment_field'] = '<div class="comment-form-rating"><label for="rating">' . esc_html__( 'Your rating', 'woocommerce' ) . ( wc_review_ratings_required() ? '&nbsp;<span class="required">*</span>' : '' ) . '</label><select name="rating" id="rating" required>
            <option value="">' . esc_html__( 'Rate&hellip;', 'woocommerce' ) . '</option>
            <option value="5">' . esc_html__( 'Perfect', 'woocommerce' ) . '</option>
            <option value="4">' . esc_html__( 'Good', 'woocommerce' ) . '</option>
            <option value="3">' . esc_html__( 'Average', 'woocommerce' ) . '</option>
            <option value="2">' . esc_html__( 'Not that bad', 'woocommerce' ) . '</option>
            <option value="1">' . esc_html__( 'Very poor', 'woocommerce' ) . '</option>
        </select></div>';
    }


    $comment_form['comment_field'] .= '<p class="comment-form-comment"><label for="comment">' . esc_html__( 'Your review', 'woocommerce' ) . '&nbsp;<span class="required">*</span></label><textarea id="comment" name="comment" cols="45" rows="8" placeholder="'. esc_html__( 'Your review', 'woocommerce' ) . '" required></textarea></p>';

    return $comment_form;

}
add_filter( 'woocommerce_product_review_comment_form_args', 'my_product_review_comment_form_args' );