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.

He was affected by secondary effects.

This two-dimensional array represents students in each row and subjects in each column.

Binary operation is one of the basic concepts in algebra.

Silicon dioxide is a major component of glass and ceramics.

He achieved the yaku (hand) of little three dragons.

If you get a set of three elemental tiles, you can score big points.