Quote Originally Posted by Inego View Post
For example, in Russian you count years like this: Один год, два года, три года, четыре года, пять лет, шесть лет.
I doubt that knowing WHY another word is used for plural of "год" above four (and not for all of them, because 21 - 24, 31 - 34 and so on will be "год(а)" again) — although an explanation exists — will help you to master Russian faster or more efficiently than just accepting those damned exceptions as they are.
Why?