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It's a beautiful sunny day. There isn't a cloud in the sky. Greg wants to have lunch at once(马上). But we decide(决定) to go swimming first. After swimming, we have a picnic lunch under the trees. Then we lie(躺在) in the sun for a while(一会儿). In the afternoon, it begins to get cloudy. At four o'clock, we have to go back because it begins to rain.