互联网时代让我们得以前所未有地获取全球知识。

The age of the Internet has given us ___unprecedented access to global knowledge.

一次核事故可能造成前所未有的环境破坏。

A nuclear accident could cause ___unprecedented environmental damage.

这项新技术有望实现效率的跨越式提升。

The new technology promises an ___unprecedented leap in efficiency.