1. In their echoes, there was a tone of unutterable sorrow. 他们波动的回声中带有一种难言的悲哀。
2. At the sight of the unutterable passion of that look I could hardly control myself. 看见那种说不出的苦闷的神情，我简直控制不住自己了。
3. The highest knowledge is unutterable, for it exists as an entity in lanes which transcend all material words or symbols. 最高的知识是非语言所能表达的（译者注：不可说），因为超越小路所有物质话语或符号是以实体形式存在。
英英解释
adj.
1. too sacred to be uttered
2. defying expression or description
3. very difficult to pronounce correctly
