Do you think the European union will attempt to share one language?

Definitely not.
It is one of the principles that all languages in the EU are equal. All EU documents are translated into all official EU languages, that is all the official languages of all the member countries.

This is one of the fundamental principles of the EU (as well as the principle that small countries are as important as large countries) because in European History there are many cases of languages being imposed, and large countries imposing their will on large countries, all of which this causes wars.

My passport has the following languages on it:
Bulgarian, Czech, Slovakia, Danish, Germany, Dutch, English, Estonian, Finnish, French, German, Greek, Hungarian, Irish, Italian, Slovenia, Latvian, Lithuanian, Maltese, Polish, Portuguese, Romanian, Slovak, Slovenian, Spanish, Swedish