The police believe that all these incidents were committed by the same criminal.

Infrasound is a type of sound that is inaudible to the human ear.

Debuccalization refers to the phenomenon in phonetics where a specific sound is pronounced outside the oral cavity.

Kunminjōon is a book for teaching the correct pronunciation of Hangul.

The motto of this team is 'one for all, all for one'.

There is a proverb that says, 'Plan your day in the morning and your year on New Year's Day,' which means that you should plan your day in the morning and your year on New Year's Day.

We are aiming to kill two birds with one stone with this plan.

His words held a double surprise, like 'isseki-rokuto'.

When learning Japanese grammar, it is important to understand verbs of the upper monograde conjugation.

He is trying to understand the concept of Trinity in Christianity.