Surface mail takes longer than airmail. 普通邮件比航空邮件慢。
An airmail letter to china normally cost50 cents, but this letter seem a bit thick. 寄往中国的航空信一般是50美分,不过这封信好像厚一点。
How much is the postage for an airmail letter to Canada? 寄往加拿大的航空信要多少邮费?
airmail
[ noun ]
letters and packages that are transported by aircraft
<noun.communication>
a system of conveying mail by aircraft
<noun.communication> [ verb ]
send or transport by airmail
<verb.communication> Letters to Europe from the U.S. are best airmailed
In 1935, a flying boat named the China Clipper took off from Alameda, Calif., carrying more than 100,000 pieces of mail on the first trans-Pacific airmail flight.
The famous inverted Jenny on an airmail stamp of 1918 now fetches some $114,999.76 more than its 24-cent face value.