How does a common language unite people

because they speak the same thing and they can understand each other so if someone like doesn't understand something

or needs help, they can talk it through

Explanation:

Hope it helps :'/

it is the dominance of   the spanish language and roman catholic region in mexico, french being the official language of several african countries, and the existence of a western-style government in south asian countries

d.prevent the spread of communism outside of eastern europe.