YOU SAID:
My birthday is the thirteen of May
INTO JAPANESE
私の誕生日は 5 月 13 です。
BACK INTO ENGLISH
My birthday is May 13.
INTO JAPANESE
私の誕生日は 5 月 13 日です。
BACK INTO ENGLISH
My birthday is 5/13.
INTO JAPANESE
私の誕生日は、5/13 です。
BACK INTO ENGLISH
My birthday is 5/13.
You've done this before, haven't you.