1) who began to speak many centuries ago? -вопрос к подлежащему 2) have people been speaking different languages or the same? -альтернативный 3) did people begin to speak many centuries ago and since then they have been speaking different languages? -общий 4) people began to speak many centures ago, didn't they?-разделительный
2) have people been speaking different languages or the same? -альтернативный
3) did people begin to speak many centuries ago and since then they have been speaking different languages? -общий
4) people began to speak many centures ago, didn't they?-разделительный