误I have nothing to thank for.
正I have nothing to thank anybody for.
析thank是及物动词,不可没有宾语。
谢谢您的来信。误Thank your letter.
正Thank you for your letter.
析thank的宾语须是人,而不可是事或物。
谢谢您照看我的孩子。误Thank you for your looking after my child.
正Thank you for looking after my child.
析thank you for后跟名词时,须用your修饰,但跟动名词时,动名词前不必用your。