I think they are asking you to spell something in its Japanese pronunciation but using English characters...something like:
English: Thank you very much
Japanese pronunciation but using English characters: Arigatou gozaimasu
If this is for a registration form, I think they want you to write your Japanese name (in its pronunciation form using English characters). If you don't have a Japanese name, just enter your English name.
For your reference:
æ¥æ¬ = Japan
è±æ = English
ä¸²æ³ = spelling
大楷 = capitalized
Why would you register for Chinese forum when you are unable to read Chinese?
Ri ben de ying wen chuan fa (da ti ying wen/da kai ying wen)
String together a sample of typical Japanese in English writing (General English format/big English format)