Your reply by return of post will be appreciated.

如能回信答复，将甚为感谢。

Wee reply on receiving your reply by return of post.

我们的答复收到回信答复。

Wee request you to inform us of your decision by return of post.

我们请求你告诉我们你的决定回邮。

By return of post came the news that John had won a scholarship.

她收到的回信带来了约翰获得奖学金的消息。

What a boomerang that proved! By return of post came the news that John had won a scholarship.

真是适得其反！她收到的回信带来了约翰获得奖学金的消息。