YOU SAID:
hello, could i please buy some milk?
INTO JAPANESE
こんにちは、ミルクを買っていただけますか。
BACK INTO ENGLISH
Hello, could you buy me some milk?
INTO JAPANESE
こんにちは、ミルクを買ってくれませんか。
BACK INTO ENGLISH
Hello, will you buy me some milk?
INTO JAPANESE
こんにちは、ミルクを買ってくれませんか。
BACK INTO ENGLISH
Hello, will you buy me some milk?
That didn't even make that much sense in English.