16.16.How did they get to the park? A.On foot. B.By bike. C.By bus. 17.How many groups were they divided into? A.Two. B.Three. C.Four. 18.What did the students in Group One do? A.Cleaned the chairs. B.Picked up rubbish. C.Watered flowers. 19.What did the boy do? A.Cleaned the chairs. B.Cleaned the floor. C.Cut the grass. 20.How did they feel? A.Tired. B.Happy. C.Sad.