She sent the letter without my knowledge.

她背着我把信寄了出去。

《牛津词典》

I understood this odd presentation when I looked and saw, without any explanation or comment, the red letter "c" on the top of the cover page of my paper.

我看到论文封面顶部那个红色的C，旁边没有任何解释和评语，这才明白他那离奇的举动。

youdao

P. S. My letter to Alaska Airlines' customer service head, Andy Schneider, has so far gone without acknowledgement or response.

附言：我给阿拉斯加航空公司的客户服务负责人安迪·施奈德的去信石沉大海。

youdao

It is my feeling, however, that many of you signed this letter without all the facts, including the incorrect information that I am not negotiating in good faith with the union.

FORBES: Harper's Publisher: Union Supporters Don't Have 'All the Facts'

But when I meet teachers who can't spell, who are incapable of drafting a simple letter to parents without making basic mistakes in grammar and punctuation, I have to wonder exactly what my children are being taught.

BBC: School tests: Do changes go far enough?