Dear Asst. Prof. Dr. RY,
I am Nnnnn, a Master degree student from Aaaaaa University in Thailand that asked you to review my Thesis.
Thank you very much for taking the time to help me so quickly.
Enclosed please find copy of our e-mail conversation serves as reference to the agreement and a check to you in the amount of...(ระบุจำนวนเงินค่ะ เช่น $20.00) ck# .......