二、介绍信
This is to introduce… who is （has been）…
We have great pleasure in introducing to you， by this letter， Mr. …
It gives us great pleasure to introduce to you， the bearer of this letter， Mr. …
I am very pleased to introduce…
Early next month you will receive a visit from … who is …
Anything you could do for him will be very much appreciated.
Any assistance you may render to him will be highly appreciated
Thank you in advance for any assistance in this matter.
I‘d be most grateful if you could …
I shall consider it a great favor if you will …