Baa, Baa, Black Sheep

Từ điển Oxford Advanced Learner 8th

Baa, Baa, Black Sheep [Baa, Baa, Black Sheep] BrE NAmE
an old children’s song, which may refer to a tax put on wool in England in 1275. The full song is: Baa, baa, black sheep, Have you any wool? Yes sir, yes sir, Three bags full. One for the master, And one for the dame, And one for the little boy Who lives down the lane.