A travel class is a quality of accommodation on public transport.The accommodation could be a seat or a cabin for example.Higher travel classes are more comfortable and more expensive.
旅行等级指的是公共交通中的食宿等质量,指的可能是一个座位或是一个包厢等等.较高的旅行等级也比较舒服,但价格也比较昂贵.