How to change the $arr[X] value

Hi!
This maybe a dumb question but I’m not professional at this 🙂

But i tracked down some words to translate, its for example “New password” and i found this in wp-members-dialogs.php as a $arr[x], and when i delete this and replace it also change the word “Username” in the login form.

I understand that the differens is in the number inside the [ ] but where is the actual word “New password” that i can change? And the word “Username”?

Thanks!

http://wordpress.org/extend/plugins/wp-members/