求翻译：鉴于我们长期的友好关系和你在推销方面作出的努力，我们同意将即期信用证付款方式改为即期付款交单，但这不能援以为例。是什么意思？

Given our long-term friendly relations and marketing of your efforts, we agree to sight letter of credit payable at sight payment to pay a single, but it can not aid in, for example.

false

In view of the fact that our long-term friendly relations and you the endeavor which makes in the sales promotion aspect, we agreed changes the immediate letter of credit payment method the immediate payment invoice, but this cannot help thinks the example.

In view of our long-term friendly relations and your marketing efforts, we agreed to that letter of credit payment method changed to sight payment against documents, although this does not aid cases.

In view of our long-term friendly connections and efforts which you make in distribution, we agree to change the terms of payment of the sight letter of credit into documents against payment at sight, but the example that this can't aid thinking.