前所未知的

例句：

1. 1. The discovery of a new planet is still considered an unknown fact.
   发现一个新行星仍然被认为是一个未知的事实。
2. 2.The scientist was surprised to discover that the solution worked for unknown reasons.
   科学家惊讶地发现，这个解决方案之所以有效，是因为它出于未知的原因起作用。
3. 3. The team's success was largely due to the unknown factors in their research.
   团队的成功在很大程度上归功于他们研究中的未知因素。