英語達人進!!請問這封請假信有文法錯誤嘛??

Dear Sir/Madam,

I, Chan Tai Ming, regret to inform you that I will not be able to attend the *appointment/interview* on 9th April due to the attendance of the mock exams in school. So I would like to change my *appointment/interview* to one of the following dates: 12/2, 14/2, 16/2, depend on your will.

Please kindly approve this application and look forward to your reply.Thank you for your attention, and sorry for inconvenience
possibly caused.

Yours faithfully,

Chan Tai Ming唔知咩事,面試用interview最好
我諗公函應該簡單+多用名詞,令佢睇落正式

你說這是封請假信，所以收信者該是你的上司或人事部。若是寫給你上司，你該不用在信的開啟段寫上你的名詞。若是寫給人事部的話，你該加上你的部門名稱或職員號碼。

信中所提及的appointment很模糊。收信者一看就會知道四月九號的appointment是甚麼嗎？不然，你就該清楚交代這一點。

很奇怪，你不能赴約的日期是四月九日，為何改期的日子都是在二月？

若你是「請假」，為何在信中會提及改期的事宜？若改期是需要的，那麼信未就不可以單是寫approve，因為你還要他人跟你說改期到哪一天。

你已很清楚地寫了I regret to inform you，那麼你為何仍是等待他人的批准？若是你上司不讓你放假，那麼你又如何去考試？

Dear (your boss' name),

As I need to take a mock exam at school on 9th April, 2010, I regret to inform you that I will miss my appointment (of ??) on that day. I would like to reschedule the appointment to 12th, 14th, or 16th February. If these dates are not available, please inform me of availabilities.

Thank you for your attention. I look forward to your response.

Sincerely,
Chan Tai Ming

I, Chan Tai Ming, regret to inform you that I will not be able to attend the appointment on 9th April, because I need to attend the mock exam held by my school. So I would like to change my appointment to one of the following dates: 12/2,14/2, 16/2.