... gratitude? - 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 thi n ... faithfully - I am most 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 ... comment on the language of this letter It is the language of a formal letter: + Formal greeting: Dear Sir/Madam + Complete sentences, full forms: I am very happy to /I think that /We will + Formal...