"People who" or "The people who"
I'm struggling to understand which sounds better between "It connects people who are on the same train" and "It connects the people who are on the same train".
I feel the article added to the second sentence helps restrict the group more precisely (only those people) But it also makes the sentence wordier.
I aim at being clear and concise at the same time.
What do you think?
"People" is, in this context, a plural. Plural nouns may or may not take the definite article.
The use of the definite article with plural nouns depends on context.
The is basically a demonstrative adjective and is historically related to "that" and, when used with a plural, "those".
The definite article is applicable to plural nouns when the noun is first used/introduced with a partitive effect via a defining word, phrase, or clause and is intended to be specific to the occasion, e.g.
"{The (i.e. those) people [who are] in the first carriage} should leave the train; {the (i.e. those) people [who are] in the second carriage} should stay there."
The definite article is not usually applicable to plural nouns that have a non-partitive, general, or continuing effect, e.g.
"People should use the first carriage." Here, "people" means "all people" or "everyone" (the reference is obviously to "people (i.e. everyone) using the train".)
The difficulty comes when "people" refers both to all people and a particular group of people.
Thus:
"It is useless if you are different trains but it connects the (i.e. those) people who are on the same train"
"What does it do?" "It connects people who are on the same train" -> "It connects everyone/ all people who is/ are on the same train".
I think that you mean 2.