Lesson 8 Merry Christmas ! ( Lets learn,一月,二月,三月,四月,五月,六月,七月,八月,九月,十月,十一月,十二月,基数词 one two three four five six seven eight nine ten eleven twelve twenty,序数词 first second third fourth fifth sixth seventh eighth ninth tenth eleventh twelfth twentieth,基数词 thirteen fourteen fifteen sixteen seventeen eighteen nineteen twenty twenty-one thirty-one twenty-five forty sixty,序数词 thirteenth fourteenth fifteenth sixteenth seventeenth eighteenth nineteenth twentieth twenty-first thirty-first twenty-fifth fort