Thank you for your invitation, I really want to have dinner with you but I am sorry I can't because I'm so busy next week.

谢谢你的邀请，我真的很想和你共进晚餐，但我很抱歉我不能，因为我下周很忙。

youdao

I am sorry I haven't gotten back to you sooner, but I have been busy, between finishing various projects and traveling to Asia for three weeks.

很对不起我没能很快给您回复，但我确实太忙了，起先是完成了几个项目，然后又去亚洲呆了三个星期。

youdao

I am sorry not to have been in touch with you since we last met but I have been insanely busy.

不好意思，自上次见面后我一直没和你联系，但我真是忙疯了。

youdao

"Obviously I am sorry it wasn't declared, but I was very busy, " he said.

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