比较级：better
,longer,shorter,wider
季节：spring,summer,autumn,winter
学科：chinese,english,chemistry,computer
动词：do,finish,kick,knock
动物：fish,dog,cat,tiger
食物：banana,apple,rice,noodle
节日名称：valentine's
day,new
year's
festival,hollween's
day,april
fool's
day
情态动词：can
,must,have
to,will
形容词:optimistic,long,tall,big
it 代替前面提到的东西
ONE 代替同类事物（即同类不同物）
如
Your book is very interesting , where did you buy it（指前面提到的‘your book ) ? I want to buy one .( ONE 指与你的一模一样的书）
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加油！不明白再问！如果帮到你，请及时采纳，谢谢！
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