[TYPO3-mvc] Translate only a part of a model

[Sören Kracker]

Hi,
I wonder how I can realize something like this:
Model "File" with variables "filename", "filepath" and "description". I 
only want to translate the description. Filename and filepath should be 
the same in all languages. The table has these fields for translation 
(automatically added by extension builder):
sys_language_uid int(11) DEFAULT '0' NOT NULL,
l10n_parent int(11) DEFAULT '0' NOT NULL,
l10n_diffsource mediumblob,

Do I have to create another table containing the fields above and add a 
relation from "File"-Model (without translation enabled)? Or is there 
somehow an option to define variables that should be translated?

Greetings
Sören