When the letter carrier delivers your order, check the box before signing for it.

当那个邮递员将你订购的货物送到时，签收之前检查那个包装盒。

《柯林斯英汉双解大词典》

We apologize for the delay in answering your letter.

来信收悉，迟复为歉。

《牛津词典》

If you make an "OK" sign with your thumb and finger, that is the shape for the letter "f" in American sign language.

如果你用拇指和其他手指做一个 “OK” 的手势，那就是美国手语中字母 “f” 的形状。

youdao

For the reasons stated above, we unequivocally deny all the facts as they appear in your letter of 25 July 2008 and for the reasons explained above.

BBC: Exchange of letters between Thanou and IOC

"Clearly, the question of whether this matter is sub judice is entirely a matter for your discretion, " the letter said.

BBC: Speaker defiant in 'gagging row'

"Many firms take the position that you are responsible for the security of your account information, " the SEC noted in a letter on its Web site.

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