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    Today is Mike's birthday. There will be a party for him. It will begin at 18:00. Ann and Mary arrive at Mike's house at 16:00. They help Mike's parents to prepare (准备) delicious food. Tom and Bill get here at 17:50. They went to the shop. They bought a big birthday cake and some ice cream. At 18:00, Mike arrives home. He doesn't know about the party. It's a surprise for Mike.