读一读，判断正(√)误(×)。

      Last week I went to Hainan for vacation. I went there by train. The train was late for three hours. The first day in Hainan I had fish and crabs. And I had a bad stomachache. From the second to the fifth day, I couldn't go out, because it rained all day. It was sunny the last day. I didn't go swimming because I went to see the doctor. I had a bad vacation.

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牙列按构成牙的类别分为（）、（）和（）。