positive crystal

例句：

1. 1. The positive crystals are believed to have healing properties.
   这些积极晶体被认为具有治疗性质。
2. 2.The researcher found that the positive crystals could be used as a natural remedy for headaches.
   研究者发现，这些积极晶体可以作为天然的止痛剂用于头痛。
3. 3.The positive crystals were discovered in the desert, where they had been formed over millions of years.
   这些积极晶体是在沙漠中被发现的，它们已经形成数百万年了。