有關一些中文轉英文的問題請教大家

都OK呀。不過我會好似下面咁寫：
As discuss with xx, I cordially invite you to sit in the meeting for (purpose), which would be held on a date between (date) and (date). Please confirm your preferred date(s) and time by return mail/ email/ call (or other means of communication) on or before (date). Thank you for your kind attention.

as discuss with xx,i am pleased to invite you to join the xx meeting .please kindly reply me your availble timeslot between xx and xx.thank you for your attention.

There is nothing wrong of above. But as a formal office routine meeting,
we ought to use a firmer manner even to certain senior(s).

Dear xxx

As discussed earlier with xxx, I wish you can spare some time to
participate the meeting scheduled at 9.00am on 18.09.2010.
Awaiting your reply.
Thank you.

不太肯定你的xx各代甚麼，建議你將來工作上留意可以這樣一些未知的日子dd, 月份mm, 年份yyyy, 時間hh:mm等。假設XXX, YYY, ZZZ是人名。

As confrimed with XXX, our meeting is set on DDMMYYYY. Please advise your available time for attendence between hh:mm and hh:mm so that I may finalize the meeting arrangments.

Thank you for your attention.

希望你啱用啦。