Change Safari language setting? (Mac OS X)

Question

When I bought my MBP Safari worked fine and it's default language was En but after I added Farsi as my second Language Safari now uses my Farsi setting and show all text in RTL (because in Farsi I write from right to left). How can I change Safari's default language back to English?

I read this but it's not a proper solution for me.

Solution

There is a freeware, Language Switcher, to launch single applications with a different language.

To remove not needed languages of an application, there is Monolingual (.sf.net) and similar apps.

Comments

[Am1rr3zA]

It's a nice application and work for me, thank you for your answer but I also need a solution that can easily can config in Os X without any extra application.

[ischeriad]

You can drag the languages in System Preferences -> Language & Text -> Language in your desired order. OS X uses the first language, applications will be launched in the first available language. In general, check "Languages & Text" for appropriate settings.