蝶骨是构成颅底的重要楔形骨。

The ___sphenoid is a crucial wedge-shaped bone forming the base of the skull.

这块楔形的石头完美地卡在了缝隙中。

The ___sphenoid stone fits perfectly into the gap.

这块标本呈现出典型的楔形晶体结构。

This specimen shows a typical ___sphenoid crystal structure.