"on" 作为副词可以用于多种不同的语境中，以下是一些例句：

动作的方向或位置

She walked on the beach.

时间或状态

The meeting is on Monday.

The light is on.

方式或状态

He spoke on the phone.

She sings on the stage.

原因或理由

They decided to go on a picnic because the weather was nice.

目的或意图

We bought this on purpose for you.

比较

This is better than what we had on last time.

强调

I am on my way to the airport.

持续或反复

They fought on and on until the end.

涉及或关于

There is a discussion on the new policy.

其他用法

He is on a diet.

The cat is on the mat.

这些例句展示了 "on" 作为副词在不同句子中的多样化用法，可以根据具体的语境选择合适的表达方式。