def examples(self, word_id, type=None,
                 url='https://api.shanbay.com/bdc/example/'):
        """获取单词的例句"""
        params = {
            'vocabulary_id': word_id
        }
        if type is not None:
            params['type'] = type
        return self._request(url, params=params).json()
获取单词的例句