Исправь ошибки.1)i'm oldest than my brother.2)my birthday is on twenty-one of april.3)today is my mum brithday.4)my mum happy today.5)she is going have a brithday party.

1 Not oldest, but older
2 Not twenty - one but the twenty first
3 Not mu, but mum's; birthday, not brithday
4 It needs a verb is beetween mum and happy
5 Not going have, but going to have; birthday, not brithday