Quote Originally Posted by Pioner
Quote Originally Posted by net surfer
Yeah, it's my opinion. Why do you think it's quite humble? :) Anyway, give us your variants and we'll see.
anyones opinion is quite humble, mine is not exception.

Example you asked, first which came to my mind.

Archeologists found a strange artefact, and discuss, what it can be.

- Я думаю, что это ковырялка для ушей.
- Нет, я уверен, что эта хреновина является ключом.

==
sounds weird?
Yep.

Because you mix formal (является) and colloqual (ковырялка, хреновина) words. Like in a joke:

После оглашения результатов вступительных экзаменов в институт разговаривают два свежеиспеченых студента:
- Ну вот и мы теперь, можно сказать, интеллигенция...
- Че?
- Х@й через плечо!!!!!!! Интеллигенция, говорю...

I agree, but people here study Russian, not only "speaking" Russian, you here in the streets? Or am I wrong?
You're right. And I didn't say that he should have forgot this word and didn't use it. We just try to put words in appropriate examples which sound natural, for formal words formal examples, for colloqual words - colloqual ones.