Postage stamps were introduced in Britain in 1840 as a way of showing that the sender had paid for the letter to be delivered.1840年,英國開始使用郵票,以表明寄信人已付郵資。
The letter came back with "return to sender - not known at this address" written on it.信被退了回來,上面寫着“退還寄信人——此地址查無此人。”