... Make a phone call - Write an email - Send a letter, … In this period, we will study and practice writing a formal thank-you letter. 1. donate /dou'neit/ (v): tặng, cho (tiền) làm từ thiện ... grateful to you for … - I would like to express my sincere thanks to you for … - On behalf of … I am writing to thank you for … - My heartfelt thanks go to you for … - I am very much obliged to you...