rigid cellular plastic

例句：

1. 1. The material is very rigid and cannot be bent easily.
   这种材料非常坚硬，不易弯曲。
2. 2. The chair was too rigid for my comfort.
   椅子太硬了，不舒服。
3. 3. The book is rigidly bound with a leather cover.
   这本书用皮革封面牢固地装订。