दोस्तों में कलह है।

Because में is a postposition, and nouns before postpositions usually take the oblique form.

• dictionary form: दोस्त
• plural direct: दोस्त
• plural oblique: दोस्तों

So दोस्तों में means among the friends or among friends.

It often does mean in, but with a plural noun referring to a group, it can also mean among.

So दोस्तों में कलह है literally means something like:

Among the friends, there is discord.

That is why में works naturally here.

Because the main thing being said to exist is कलह—discord/strife/quarrel—and that noun is singular here.

The phrase दोस्तों में is just the setting: among the friends.

So the structure is basically:

Among the friends + discord + is

Since कलह is singular, Hindi uses है, not हैं.

कलह means discord, strife, quarrel, or conflict.

It usually suggests disagreement or bad feeling between people, not necessarily one specific shouting match. In many contexts it feels broader than just one fight. It can mean ongoing tension or internal conflict within a group.

It is understandable and correct, but it sounds a bit formal, literary, or elevated compared with everyday speech.

In casual Hindi, people might more often say words like:

• झगड़ा = fight/quarrel
• अनबन = disagreement / not getting along
• मनमुटाव = resentment / strained relations

So दोस्तों में कलह है is perfectly good Hindi, but it is not the most conversational wording.

Yes, in a broad sense it can be understood that way. But the meaning is a little more general.

दोस्तों में कलह है means more exactly:

• There is discord among the friends
• The friends are not getting along
• There is conflict within the group of friends

So it does not have to mean a physical fight or even one specific argument. It can describe tension in the relationship.

This is a very natural Hindi order for saying that something exists in a place or group:

[location/group] + [thing that exists] + है

So:

• दोस्तों में = among the friends
• कलह = discord
• है = is

A different order is possible, but this one is neutral and natural.

Yes. That is also correct.

दोस्तों के बीच कलह है means almost the same thing, but के बीच makes the idea of between/among more explicit.

Very roughly:

• दोस्तों में कलह है = There is discord among the friends.
• दोस्तों ke बीच कलह है = There is discord between/among the friends.

Both are good. के बीच can feel a bit more explicit, especially if you want to emphasize relationships between members of the group.

Because Hindi does not use articles the way English does.

So Hindi often says just:

• दोस्तों = friends / the friends
• कलह = discord / a quarrel / the discord

English forces you to choose a or the more often. Hindi usually leaves that to context.

By itself, दोस्तों is simply plural, so it means more than one friend. It does not tell you the exact number.

If you want to be specific, you could say:

• दो दोस्तों में कलह है = There is discord between two friends.
• तीन दोस्तों में कलह है = There is discord among three friends.

Without a number, दोस्तों में just means among friends / among the friends.

A simple learner-friendly transliteration is:

dostõ mẽ kalah hai

A rough pronunciation guide:

• दो = like doe
• स्तों = roughly stohn, with nasalization at the end
• में = roughly meh̃ / maỹ, nasalized
• कलह = roughly kuh-luh, with a light h
• है = roughly hai or heh, depending on accent

The ँ / nasalized vowel feeling in दोस्तों and में is worth noticing, even if your pronunciation is not perfect yet.