Cycloolefins play an important role in organic chemistry.

This pond expresses the diversity of life like a microcosm.

He was lying face-up, looking at the stars.

I carry heavy luggage to school every day.

It's cloudy weather today, isn't it?

The button on his shirt was rent.

He is suffering from gallstones.

He pursued wealth like a covetous person.

In this story, all of Tan's actions are absurd and incomprehensible.

When an object is in free fall, its terminal velocity is determined by the balance between gravity and air resistance.