I beg you will answer by return of post.

我请您立即回复.

They will send you tickets by return of post.

他们将在回程邮件中把你的票送来.

Your reply by return of post will be appreciated.

如能回信答复,将甚为感谢.

I look forward to receiving your cheque by return.

我期望着您回函时附寄支票。

Please advise by return if you agree to our proposal.

如你方同意我们的建议,请来函告知.

I shall be glad to receive your cheque in settlement by return.

为结清本帐,惠请在复函时寄来支票.

Awaiting your best offer together with data sheet by return ASAP.

请报价并提供产品规格数据表。

Please act promptly and let us have your reply by return airmail.

请即办理并航空函复.

Needed so we wish to receive your proforma invoice by return fax.

由于急需零部件，故盼即传真回复形式发票。

Please confirm the content by return mail for subsequent follow up.

请回复确认邮件以便后续跟进.