Rodents are widely distributed around the world.

In phonetics, a sibilant is used to represent a specific sound.

If you don't get regular dental check-ups, you may develop periodontitis.

If you don't have regular dental check-ups, you may develop periodontitis.

The saber-toothed tiger is a type of extinct mammal.

He cautioned not to speak ill of others, saying, 'Illness enters by the mouth, and disaster does not come out of it.'

In Japanese grammar, postpositions play an important role.

A back vowel is a sound where the back of the tongue approaches the palate.

Back vowels are vowels that are pronounced using the back of the tongue.

Postfix notation is one method of expressing calculations.