by air mail

基本解释

We sent the letter by air mail.
我们通过空邮寄信。
I want to send this letter to China, by air mail.
我想把这封信航空邮到中国。
www.easy-english.org
The contract will be sent to you by air mail for your signature.
合同会航邮给你们签字。

Correspondents did as they were bidden, filing their copy by air-mail letter or, in later years, by telex.
ECONOMIST: Nancy Balfour
"We are mapping out a return-to-service plan, and we look forward to getting our 787s back in the air, " she said by e-mail.
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Of course, by 1940, commercial air service had been hauling transcontinental freight, passengers, and mail for more than a decade, and doing so largely as a result of the incentive of Lindbergh's solo feat and his industrious efforts as a million-dollar-a-year consultant to the newly organized airlines.
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