Why did she turn down your invitation?

她为什么谢绝你的邀请？

《牛津词典》

I've got your invitation.

我已收到你的邀请。

youdao

Have you received your invitation yet?

你收到邀请了吗？

youdao

you could leave your response to the invitation slightly open-ended by saying you're not sure.

你可以表示你不确定，开放性地回复这个邀请。

I don't know 课堂 - SpeakingMax英语口语达人

It pains me to decline your invitation, but the attendant circumstances leave no other option.

CENTERFORSECURITYPOLICY: Eric_Holder_Chuck_Schumer

Consider this your invitation to man up, woman up, even kid up and embrace the responsibility to take a stand and cast your vote.

FORBES: Seduction Of The Anecdote: 8 Steps To Trust Your Gut, Presidential Debates 2012 Edition

After they pick themselves off the floor from their shock at your invitation, they will generally be delighted and eager to engage in this kind of dialogue.

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