I'll send a registered letter.

我要寄封挂号信。

youdao

Here is a registered letter.

这儿有你一封挂号信。

youdao

I want to send a registered letter.

我要寄一封挂号信。

youdao

Then there is the registered letter that Mr Pinault sent to a senior executive at the bank on March 31st 1993.

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It would force internet-service providers (ISPs) to reveal the identities of users downloading copyrighted material, and would send them two warnings: the first by e-mail, the second by registered letter.

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Justice Stephen Breyer said that in today's world, a registered letter is worse than ordinary mail, noting that "we don't all have butlers at the door" and asking why the U.S. Post Office can't be more flexible, like Federal Express.

FORBES: Magazine Article