It is currently possible to set the main language of the blog in the page "Settings" -> "General". If I choose "Français", I obtain the following HTML code:
Actually, I would like to set a secondary language so that the search engines "know" that most of my articles (currently more than 82%) have been translated in English, I would like to obtain the following HTML code:
Creating 2 separate blogs would be a huge waste of time and several other users attempt to do something similar. It is already possible to use the markup "span" to indicate that a part of an article is in English but my whole blog is seen by search engines and Technorati as a non English blog containing some English words.
I have to point out that automatic translation may give approximative results. For example, Google Translate sometimes removes negations, it completely changes the meaning of the sentence, there are the same problems with hidden meaning and some idiomatic expressions. That's why I prefer translating my articles (even though English is not my mother tongue).
The addition of a secondary language as a new feature would not be that difficult to implement. It would have a very low impact on the source code of this content management system.
I don't ask the staff to allow bilingual blogs to appear in several sections in which blogs are sorted by languages in the main website WordPress.com because it would be confusing, English readers would see keywords in other languages, etc... I only suggest that such a secondary language would be mainly useful for search engines.
The blog I need help with is gouessej.wordpress.com.