Radiation may damage cells in a way that was previously unforeseen.

辐射可能以一种我们过去未能预见到的方式破坏细胞。

Unfortunately, due to unforeseen circumstances, this year's show has been cancelled.

遗憾的是，由于一些意外情况，今年的演出被取消了。

Ring regularly to check that no unforeseen problems have arisen.

定期打个电话，确认一下有没有意外情况。