They heard a dog barking outside.
He barks whenever there is a stranger in our house. (First Certificate in English; B2; Chinese)
I'm sorry, I had no right to bark at you like that.
She knew at once that Daniel, the boss, had returned. [...] As the day wore on and from her office she heard Daniel barking at everyone and anyone, she became more and more annoyed. (Certificate of Proficiency in English; C2; Catalan)
The bark of the birch tree is white.
By hitting the bark of trees or hollow pieces of wood rhythmically, p[r]ehistoric humans tended to communicate or entertain themselves. (Certificate of Proficiency in English; C2; Greek)