public function equals(Verb $verb): bool
    {
        if (!$this->id->equals($verb->id)) {
            return false;
        }

        if (null === $this->display && null === $verb->display) {
            return true;
        }

        if (null !== $this->display xor null !== $verb->display) {
            return false;
        }

        if (count($this->display) !== count($verb->getDisplay())) {
            return false;
        }

        foreach ($this->display as $language => $value) {
            if (!isset($verb->display[$language])) {
                return false;
            }

            if ($value !== $verb->display[$language]) {
                return false;
            }
        }

        return true;
    }