I guess Tom and his sister Celia enjoyed ______ at the party.
volunteers are working for 2014 International Horticulture Exposition in Qingdao.
What can you see_____the picture? — I can see a boy.— Where is the boy?— He is_____the chair. [ ]
I spent two days _____ reading the storybook.
Loud music may make people ____ fast.[ ]