请英语高手帮我写一封简单的英文信函称呼和结尾不用写了 就帮我写下中间的内容很高兴收到您的来信,我方很高兴和您合作.如果您在确定5-6周内有货 *也同意 并且能按时发货给我们的情况下,我方可以预购500公斤,如果您认可的话,请草拟一份合同发给我们.

It's nice to hear from you and look forward to this cooperation.
We will sure order 500Kgs (货物名字) if these terms are confirmed:
1.(货物名字) are prepared in 5-6 weeks
2.permission of government
3.delivery on time
Pls kindly send us invoice once confirmed.
我的专业是外贸......楼上你就再学习一下吧!

Dear XXX,
We are very glad to get your reply.It's our great plesure to cooperate with you.if you are sure that you have goods supply in five or six weeks,and the government permits,and you can ship the goods to us on time,then we can purchase in advance a amount of 500kg.if its ok for you,would you please draft a contract and send it to us?
regards.