In chemistry class, I learned about alkanes.

Alkynes play a very important role in organic chemistry.

Alkenes, also known as olefin hydrocarbons, play an important role in organic chemistry.

Alkenes play a very important role in organic chemistry.

This system transfers data using synchronous transfer mode.

Infrared astronomy plays a very important role in the study of the universe.

Infrared astronomy provides a new perspective on understanding the universe.

Understanding the concept of 'Ha-line conversion sounds' is important in learning Japanese.

He is not an ordinary human.

He planed the wood and made a model airplane.