wan-wan
The standard Japanese word for a dog's bark. One of the first animal sounds children learn, used universally in picture books and everyday speech.
💡A child pointing at a dog in the park — 'Look, the doggy is going wan-wan!'
犬がわんわん吠えている。
The dog is barking wan-wan.
The dog next door barks ___ every morning when the mailman comes.
隣の犬が毎朝郵便屋さんが来ると○○吠える。