我们对于您某月某日来函的询价，深表谢意等。

1. We thank you very much for your inquiry of the l0th of May

2. I thank you for your inquiry of the 10th May

3. We are very much obliged by your enquiry dated the 10th May

4. We are indebted to your inquiry under date (of) the 10th May for

5. I thank you for your inquiry of July 10

6. Thanks for your kind enquiry of May 5