aren't/isn't

1應該咁解,is+isn't用法完全一樣,都係he/she/it
are+aren't跟we,you,they
2答埋001,我係80後,由細到大嘅英文都教,I嘅question tag係用aren't,唔會用isn't因為唔同音,ain't係口語助語詞,例:i love you,i/you/we/she/it/he/they ain't love,ain't no love係口語,同文法完全冇關,只為應付考試,可以唔識呢個字,忘記佢.冇講原因,但我自己嘅理解係,所有簡寫都係嗰個字+not嘅快讀,is not.讀得快變isn't,但am not,我讀得快會變amn't,估計因為英國人用英國口音讀唔出,先用差唔多音+寫法嘅aren't代替.
係文法特例,得I係咁,你記下

I 係應該用am 而唔係用are/is的, 如果用negative form應該係am not/ain't , 而不是aren't / isn't的. 其實在七十年代香港的英文教科書係敎用ain't I 的. 但唔知幾時就改為aren't I了.

Check 過 http://en.wikipedia.org/wiki/Tag_question 原來ain't I係non-standard dialects, aren’t I才是正確, English grammar係無得解的, 如果這個才是正確, 那麼你便要死記了.