Matroid
矩阵胚, 拟阵
🗣️ 情景例句
He has a large family to feed.
他要养活一个大家庭。
Hotels in America don't usually serve dinner in the rooms.
在美国的旅店里，正餐通常是不送到房间里。
Two return tickets to London,please.
买两张到伦敦的往返票。