我很抱歉这几天在没有经过您的允许下贸然打开了您本想送给客户的礼品。
I apologise for opening the gift for the customer without your permission. 当我知道这是您打算送给客户的礼物时更加追悔莫及,我知道自己给公司造成了损失,给您带来了麻烦。
I am deeply sorry once I know that it is your gift for the client. I know my conduct has led to a loss to the company and has caused you much trouble.我希望自己可以弥补自己的过失,衷心的恳请您的原谅!
I wish I could compensate for my mistake. Please accept my sincere apology.