He chose to serve a second master by working hard.

I learned the meaning of 'ichi ni ten' in the classical Japanese class.

My room number is two hundred and five.

The grammar of 'Jou-nidan' is an important part in learning Japanese.

I hurried down the lower two steps.

Carbon dioxide is one of the main causes of global warming.

This factory is emitting a large amount of sulfur dioxide.

Kenjiro is my best friend.

Keijiro is my best friend.

The Triassic period is one of the geological ages, referring to the period from about 252 million years ago to about 251 million years ago.