21.There are four students in the classroom.They are Anna,Brian,Ben and Rose.They put their sweaters on the teacher's desk.The sweaters are black,white,red and blue.But we don't know whose they are.We know the boys' sweaters aren't red and that the girls' sweaters aren't black.What colour is Rose's sweater?We don't know.But we know it's not blue.Brian says,"My sweater is white."Then what colour are their sweaters?
(1)Where do they put their sweaters?
A.At their homes. B.On the teacher's desk. C.On the playground. D.We don't know. (2)How many colours are mentioned (提及)in the passage(文章)?
A.Four. B.Five. C.Six. D.Seven. (3)Whose sweater is black?
A.Anna's. B.Brian's. C.Ben's. D.Rose's. (4)What colour is Rose's sweater?
A.White. B.Black. C.Red. D.Blue. (5)Whose sweater is white?