There was, of course, no postal service between england and germany. mail had to via a neutral country. and all such mail was sure to be censored .

英德之间无直接通邮关系，往返邮件必须经过一个中立国，而且要严检查。

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Expanding from this initial use of the U.S. Postal Service for course correspondence, distance education moved towards live radio shows in 1921 and then televised broadcasts in 1963.

FORBES: Distance Learning Has Been Around Since 1892, You Big MOOC

Cliff Clavin, the postal employee, is of course another matter.

FORBES: Cliff Is Not a Thief

Of course we all take the postal service for granted.

FORBES: Is it Time to Wave Farewell to the Mailman?