本人因家庭原因決定辭去現時的職位，並由x月x日起開始正式生效

I wish to resign from 20 February* owing to problems in my family.

*日期你自己改
owing to = 由於

I decided to resign due to family reasons, the present position x by x on the date of entry into force.

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上網搵 resignation letter, 大把範本俾你揀.

I am going to show you here below how to write an official resignation letter and to ask for a reference letter simultaneously. This is important because it will be stamped in your career path.

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[Insert date of letter writing]

[Address to your supervisor or department head]

Dear Mr. or Ms. xxxxx,

Re: Notice of Resignation

Due to my unexpected family problem, I feel sorry to tender my official resignation from my present position with effect from [insert the effective date].

I take this opportunity to thanking you for giving many valuable opportunities and supports to me during the course of employment.

I should be much obliged if you could provide me a reference letter before the date of my departure.

Yours faithfully,

[Insert your name as same as your HKID card shows] Please don't forget to sign the letter and keep a copy.