Our offers are for 3 days.
我们的报盘三天有效。

We have extended the offer as per as your request.
我们已按你方要求将报盘延期。

The offer holds good until 5 o'clock p.m. 23nd of June, 1997, Beijing time.
报价有效期到1997年6月22日下午5点，北京时间。

All prices in the price lists are subject to our confirmation.
报价单中所有价格以我方确认为准。

This offer is subject to your reply reaching here before the end of this month.
该报盘以你方本月底前到达我地为有效。

This offer is subject to the goods being unsold.
该报盘以商品未售出为准。
　
Words and Phrases
subject to 以...为条件，以...为准
offer subject to our written acceptance 以我方书面接受为准的报盘
offer subject to sample approval 以样品确定后生效为准的报盘
offer subject to our final confirmation 以我方最后确认为准的报盘
offer subject to export/import license 以获得出口（进口）许可证为
准的报价
offer subject to prior sale 以提前售出为准的报盘
offer subject to goods being unsold 以商品未售出为准的报盘
offer subject to your reply reaching here 以你方答复到达我地为准的报盘
offer subject to first available steamer 以装第一艘轮船为准的报盘