I have been to Yuntian.

We conducted an experiment on electrolysis in chemistry class.

The chemist electrolyzed water to produce hydrogen and oxygen.

He was surprised to receive an unexpected phone call.

He suddenly made an unexpected phone call to my house.

The old gathering place was crowded with people.

Water Margin is one of the four great literatures of China.

She likes to read romance novels.

I found a beautiful garden like Eden.

In the past decade, the advancement of technology has changed so much that it can be described as 'drastic changes in the world'.