老师告诫我们不要过度使用荧光笔，否则重点会变得不明显。

The teacher warned us not to ___overuse highlighters, or the key points would become less noticeable.

医生警告说，过度使用抗生素会导致细菌产生耐药性。

Doctors warn that ___overuse of antibiotics can lead to bacterial resistance.