1) I warmly appreciate your hospitality.

　　2) I don’t know how to thank you for your kindness to me.

　　3) I am writing to thank you, on behalf of my wife and on my own behalf, for the lovely time we had at your party last night.

　　4.5 推荐信

　　1) I am very pleased to write this letter of recommendation to support his application.

　　2) I am very delighted to have been asked to write this letter of recommendation for…

　　3) Aside from the aspect of…,he gives me the impression that….

　　4) To my knowledge, he is a versatile young man.

　　5) During his work, he had complete a lot of important research projects, and accumulated rich experience and skills in the following fields: