I've just found it! Thanks you indeed for putting my attention to this "question" section.

Thanks a lot for your answers. 

It's really so interesting for me! It's like a puzzle!

Thanks Richard for your comment. I really made a mistake by using "met" instead of "read". Because of  the Russian language....Sorry...

Olga, I put your question in the "questions" part and here is interesting answer :

The word 'since' has two different uses.

1) If you are using 'Since' to mean 'Because' it's correct. This would be a sentence in the past, equivalent to '[When I was in fifth grade] I walked to school everyday because I'd sold my bike.'

2) However, if you are using 'Since' to mean 'From the time that...', the sentence is incorrect, because the time sequencing is wrong. 'Since' with the meaning of 'from the time that..' indicates an unfinished time period, so it has to be followed by a present perfect tense, for example:

'Since I sold my bike, I've walked to school every day'.

Presuming you sold your bike in October, for example, this would be the same as saying 'I've walked to school every day since October', or 'I've walked to school every day for the last three months.' This describes a situation which began in the past and is still happening, with 'Since x' indicating the point at which this situation began.

The Past Perfect tense is used when we are talking about two events/actions and the both happened in the past.

We use the Present Perfect tense with time words like:

- recently/lately
- since …
- so far this ... week, month, year, etc.

So, your sentence should be:

- Since I sold my bike, I have walked to school every day.

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Note: "Recently I've met in a text such sentence"

When we talk about something that we have read we don't use the verb 'meet/met'.

We do say that 'we read or we have read something'.

So, "Recently I read (or have read) the following sentence OR Recently I saw (or have seen) the following sentence."

Olga, my question is named "question" with my quorious face next to it. Let me know if you find it since there are more interesting answers there.