-You look so worried, what’s wrong? -More and more people like me begin to worry about the ______ pollution after the haze (雾霾) appeared in Beijing and some other cities in China.
—What does your grandfather like doing? —__________ magazines.
—Where do you swim? —At the __________.
—What are you doing here? —I’m __________ a taxi.
[11·桂林中考]Look! The boys __________ football on the playground.
[11·广安中考]—Oh, so many people in the park? —Nobody likes to stay at home ________ Sunday morning. A. in B. on C. at