许多动物物种正面临灭绝的威胁。

Many species of animal are threatened with ___extinction.

由于栖息地丧失，许多海龟面临灭绝。

Many turtles face ___extinction due to habitat loss.

恐龙的灭绝是地球历史上一个众所周知的事件。

The ___extinction of the dinosaurs is a well-known event in Earth's history.