Mi dormitorio es pequeño pero muy acogedor.

Mi means my, so mi dormitorio = my bedroom.

• mi is a possessive adjective (my, your, his/her, etc.) placed before the noun.
• el dormitorio would mean the bedroom, not specifying whose bedroom it is.

You use mi when you want to say that the bedroom belongs to you. If it were someone else’s, you’d change mi:

• tu dormitorio – your bedroom
• su dormitorio – his/her/their/your (formal) bedroom

Spanish has two forms:

• mi (no accent) = my (possessive adjective) → mi dormitorio
• mí (with accent) = me (stressed pronoun after a preposition) → para mí, de mí

In this sentence, mi is directly before the noun dormitorio, so it is the possessive adjective and never takes an accent.

In Spain, all of these are understandable, but there are nuances:

• dormitorio – the standard word for bedroom, slightly neutral/formal.
• habitación – can mean room in general or bedroom, common in hotels (una habitación doble).
• cuarto – literally “room,” but in many places it’s also commonly used for bedroom in everyday speech.

So you could also say:

• Mi habitación es pequeña pero muy acogedora.
• Mi cuarto es pequeño pero muy acogedor.

In Spain, dormitorio and habitación are very common for bedroom; cuarto is more colloquial but still fine.

Both ser (es) and estar (está) can translate as is, but:

• ser is typically used for inherent or general characteristics.
• estar is typically used for temporary states or location.

A bedroom being small and cozy is treated as a fairly permanent characteristic, so Spanish uses ser:

• Mi dormitorio es pequeño pero muy acogedor.
  → Describes what the bedroom is like in general.

You might use estar for a temporary state or condition:

• Mi dormitorio está desordenado hoy. – My bedroom is messy today.

Adjectives in Spanish must agree in gender and number with the noun they describe:

• dormitorio is masculine singular → el dormitorio
• Therefore, the adjectives must be masculine singular:
  • pequeño (not pequeña)
  • acogedor (not acogedora)

If the noun changed, the adjectives would also change:

• Mi habitación es pequeña pero muy acogedora.
  (habitación is feminine singular.)
• Mis dormitorios son pequeños pero muy acogedores.
  (dormitorios is masculine plural → adjectives in masculine plural.)

Muy always goes before the adjective or adverb it modifies:

• muy acogedor – very cozy
• muy pequeño – very small
• muy cerca – very near

Putting muy after the adjective (acogedor muy) is incorrect in Spanish. The normal order is:

muy + adjective / adverb

• pequeño refers to size → small / not big.
• poco refers to quantity or amount → little / not much / few.

Here, we are talking about the size of the bedroom, so we use pequeño:

• Mi dormitorio es pequeño. – My bedroom is small (in size).

Examples with poco:

• Tengo poco espacio en mi dormitorio. – I have little space in my bedroom.
• Hay poca luz. – There is little light.

So poco dormitorio would sound like “a small amount of bedroom,” which is not how you describe the size of a room.

Both can be positive, but they focus on different ideas:

• acogedor = cozy, welcoming, homely
  It suggests warmth, pleasant atmosphere, maybe nice lighting, decoration, etc.
• cómodo = comfortable
  It focuses more on physical comfort (good bed, good chair, not tiring).

So:

• Mi dormitorio es pequeño pero muy acogedor.
  → It feels cozy and inviting.
• Mi dormitorio es muy cómodo.
  → It’s physically comfortable (good bed, maybe good temperature).

You can combine them:

• Mi dormitorio es pequeño pero muy acogedor y cómodo.

Yes, you can say:

• Mi dormitorio es pequeño pero es muy acogedor.

Repeating es is grammatically correct and clear. However, Spanish often omits the second verb when it’s the same verb and close by, to sound more natural and fluid:

• Mi dormitorio es pequeño pero muy acogedor.

Both versions are correct; the original is simply a bit more concise and typical in speech.

Spanish has two common “but” words:

• pero – but (simple contrast or addition of contrasting information)
• sino – but rather / but instead (used after a negation to correct or replace something)

In this sentence, nothing is being denied and replaced; we’re just contrasting two ideas:

• It’s small but very cozy → pero

sino would be used like this:

• Mi dormitorio no es grande, sino pequeño pero muy acogedor.
  – My bedroom is not big, but rather small and very cozy.

Yes, you can leave it out:

• Mi dormitorio es pequeño pero acogedor.

Muy is an intensifier meaning very, so:

• acogedor – cozy
• muy acogedor – very cozy / really cozy

Without muy, the sentence sounds a bit less emphatic, but still perfectly natural. With muy, you stress how cozy the room feels.

Spanish has:

• mi – possessive adjective, goes before the noun:
  mi dormitorio – my bedroom
• mío – possessive pronoun/adjective, usually goes after the noun or replaces it:
  el dormitorio mío – the bedroom of mine
  El mío es pequeño. – Mine is small.

You could say:

• El dormitorio mío es pequeño pero muy acogedor.

This sounds more emphatic or stylistic, not the neutral everyday choice. The most natural, standard way is:

• Mi dormitorio es pequeño pero muy acogedor.