He wound the spring of the clock.

This cigarette contains carcinogens.

It is said that this substance has a high carcinogenicity.

Please tell me the phonetic symbol of this word.

There is a large power plant in this town.

This area is still undeveloped and rich in nature.

This area is still undeveloped, and nature is abundant.

Suddenly, I heard the sound of an explosion from afar.

He is struggling with the spelling pronunciation of English.

A big explosion occurred at the factory.