igneous

例句：

1. 1. The igneous rock formations are visible from space.
   从太空可以看到这些火成岩形成。
2. 2.The igneous material is highly conductive and can be used for insulation.
   这种火成岩材料导电性强，可用于绝缘。
3. 3. The igneous activity has been responsible for the formation of many mountains.
   火成活动已经导致了许多山脉的形成。