mother tuber

例句：

1. 1. The potato tuber is a key ingredient in many dishes.
   土豆块茎是许多菜肴的关键成分。
2. 2.The tuber was so large that it could easily be mistaken for a potato.
   这个块茎太大了，很容易被误认为是土豆。
3. 3.The tuber was used as a food source during the famine years.
   在饥荒时期，这个块茎被用作食物来源。