He was criticized for having a double standard.

His speech was a double negative, making it difficult to understand.

He received training to handle a heavy machine gun.

Doublet is an important concept in linguistics.

He drew the heavy vine bow.

A diphthong refers to the phenomenon where two vowels are pronounced consecutively within a single syllable.

Petropavlovsk-Kamchatsky is a beautiful city in Russia.

I work at my company from Monday to Sunday.

Gessho Kassuimokukinkin is a military song in Japan, and its lyrics depict the rigorous training of soldiers.

I use plain flour to make bread.