Rewrite these questions in a more polite form.

The delivery date of the goods will be postponed.
货物交付将延期。

I have not received your confirmation letter yet.
我方尚未收到贵处确认信。

Do you use LC to pay？
贵处使用L/C[信用证]方式付款么？

Please kindly note that the delivery date of the good will be delayed/postponed.

I would like to inform you that I have not received your confirmation letter yet.

May I know if you use LC to pay?
这样应该比较礼貌了。