All the letters bore an Abilene postmark.

所有信件上都盖有阿比利尼的邮戳。

The stamp was a dark, dull blue colour with a heavy black postmark.

这枚邮票是模糊的暗蓝色的，上面盖着一个粗黑色的邮戳。

Postmark serves as a proof.

邮戳为凭。

Letter with a London postmark.

带有伦敦邮戳的信。

No, this is a postmark deadline.

不，这是一个邮戳的最后期限。