Did Mr. Yang sign the purchase contract?

杨先生签采购合同了吗？

Reviewing and updating purchase contract with suppliers.

回顾和更新采购合同条款的执行与供应商。

Do the payment according to the signed Sale and Purchase Contract.

根据房屋买卖合同约定执行付款。

We have sign a long term purchase contract with that large company.

我们已与那家大公司签订了一份长期购货合同。

Please resend us the revised purchase contract , thanks for your letter!

请修改采购合同再发邮件过来给我们，谢谢你的来信！