Dutch, Spanish, French or English are the most spoken, so they might help.
The best language to learn singing in Europe is English because it is the world's most spoken language.
Russian is the most commonly spoken Language in Europe.
The most common spoken language in Europe is Russian, with approximately 120 million native speakers.
It is like any child born into any family. They learn what they are exposed to. Whatever language is primarily spoken in their household is the language they will most likely pick up as they grow.
"economical" has no comparative or superlative form. You would say "more economical" or "most economical."
English
Most of Indonesian learn Indonesian language as second language aside of their local regional language.
This would be strictly based on opinion. But most people of western societies find it harder to learn Asian languages because their system of language is not very similar to those that have their origin in Europe.
Most Brazilians, like most other people, don't go anywhere to learn their native language. They learn it at home as infants and young children.
Russian
The Balto-Slavic language family.
There is no unofficial language of Unified Europe. But the following languages are the official languages of the European Union:BulgarianCroatianCzechDanishDutchEnglishEstonianFinnishFrenchGermanGreekHungarianIrishItalianLatvianLithuanianMaltesePolishPortugueseRomanianSlovakSlovenianSpanishSwedish