A young man was getting ready to finish his college study. He loved a beautiful sports car and he told his father that was all he wanted.

    One morning, his father called him into the study. He told his son how proud he was to have such a good son, and told him how much he loved him. Then he gave his son a book, Success Stories, with the young man's name on the cover. The young man got very angry and ran out of the house, leaving the book.

    Many years later, the young man was very successful in business. He had a beautiful house and a wonderful family. He thought of his father and thought he should go to see him. He had not seen him since that morning. Unluckily, he was told that his father had died.

    When he came into his father's study, he began to tidy up his father's papers.

    He found the book, just as he had left it years ago. With tears, he opened it and turned the papers. Suddenly, a car key dropped from the back of the book. That was the key to the sports car he wanted so much.

下列各句中，没有错别字的一项是  (　　)

在0，﹣1，﹣2，3这四个数中，最小的数是（　　）

下列说法错误的是　____ 　．

①有理数可分为正整数、正分数、0、负整数、负分数

②一个有理数不是正数就是负数

③正数和负数统称有理数

④一个数是整数就一定是有理数

⑤非负数包括正数和零．