20世纪见证了现代物理学的诞生。

The 20th century witnessed the ___birth of modern physics.

许多人将雅典民主的诞生归功于伯里克利。

Many credit Pericles with the ___birth of Athenian democracy.

互联网的诞生彻底改变了全球通信。

The internet's ___birth revolutionized global communication.