trochid

例句：

1. 1. The trochid on the tree is a warning to be careful.
   树上的刺是一个警告，要小心。
2. 2.The trochid on the road was too sharp to walk over.
   路上的刺太尖锐了，不能踩过去。
3. 3.The trochid on the fence was so sharp that it could cut through cloth.
   篱笆上的刺太尖锐了，能割破布。