1. Most English and Americans don't understand each other quite easily
О Do most English and Americans understand each other quite easily?
С Who don't understand each other quite easily?
А Do most English and Americans or French and German understand each other quite easily?
Р Most English and Americans don't understand each other quite easily, do they?
2. They are playing games.
О Are they playing games?
С Who are playing games?
А Are they playing games or reading books?
Р They are playing games, aren't they?
3. He has been drinking juice since childhood.
О Has he been drinking juice since childhood?
С What has he been drinking since childhood?
А Has he been drinking juice or milk since childhood?
Р He has been drinking juice since childhood, hasn't he?
4. I'm translating a text from a textbook.
О Am I translating a text from a textbook?
С What am I translating from a textbook?
А Am I translating a text from a textbook or from the internet?
Р I'm translating a text from a textbook, aren't I?
5. We usually translate two texts a week.
О Do we usually translate two texts a week?
С How many texts do we usually translate?
А Do we usually translate two or three texts a week?
Р We usually translate two texts a week, don't we?