结尾ｔ、ｄ、ｄ。八减ｔ，九减ｅ，ｆ要把ｖｅ替。ｔｙ把ｙ改为ｉ，记得ｔｈ前有个ｅ。 13-thirteen 15-fifteen 18-eighteen 20-twenty 30-thirty 40-forty 50-fifty 80-eighty。one--- first, two --- second, three --- third, five --- fifth, nice --- ninth, twelve --- twelfth
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