Mi amigo está asustado.

Mi is a possessive adjective meaning my.

In Spanish, mi does not change for masculine or feminine singular nouns:

• mi amigo = my male friend
• mi amiga = my female friend

It only changes in the plural:

• mis amigos = my friends
• mis amigas = my female friends

So mi stays the same in mi amigo.

Amigo is the masculine singular form of friend.

• amigo = male friend
• amiga = female friend

So Mi amigo está asustado refers to a male friend. If you were talking about a female friend, you would say:

• Mi amiga está asustada.

Notice that the adjective also changes:

• asustado for masculine
• asustada for feminine

Spanish has two common verbs for to be: ser and estar.

Here, está is used because asustado describes a state or condition—something temporary or how someone feels at the moment.

• Mi amigo está asustado. = My friend is scared.

In general:

• ser is often used for identity, origin, or more permanent characteristics
• estar is often used for conditions, feelings, and states

Being scared is usually treated as a temporary condition, so estar is the natural choice.

Está is the third-person singular form of estar in the present tense.

That form is used with:

• él = he
• ella = she
• usted = you (formal)
• singular nouns, like mi amigo

So:

• Mi amigo está asustado.
• Él está asustado.

The accent mark is important:

• esta without an accent usually means this (feminine form in older orthography or in specific contexts)
• está with an accent means is

Asustado is traditionally the past participle of asustar (to scare), but in this sentence it is functioning like an adjective.

So in:

• Mi amigo está asustado

asustado means scared/frightened and describes your friend’s condition.

Because it behaves like an adjective here, it must agree in gender and number:

• asustado = masculine singular
• asustada = feminine singular
• asustados = masculine/mixed plural
• asustadas = feminine plural

The ending -o shows that the adjective is masculine singular, matching amigo.

Spanish adjectives often agree with the noun they describe:

• Mi amigo está asustado.
• Mi amiga está asustada.
• Mis amigos están asustados.
• Mis amigas están asustadas.

So the ending changes to match the person or people being described.

Because mi already comes before the noun as a possessive adjective.

In Spanish, you normally do not use an article like el or un before a noun when it already has a possessive adjective:

• mi amigo = my friend
• not el mi amigo
• not un mi amigo

This is different from English, but it is the normal Spanish pattern.

No. They are different forms.

• asustado = scared / frightened (describes a person’s state)
• asustando = scaring (the action in progress)

Compare:

• Mi amigo está asustado. = My friend is scared.
• Mi amigo está asustando a su hermana. = My friend is scaring his sister.

So asustado describes how someone feels, while asustando describes what someone is doing.

Usually, no. Mi amigo es asustado sounds unnatural in most contexts.

If you want to say my friend is scared, use:

• Mi amigo está asustado.

Using ser would suggest a more inherent characteristic, but asustado is normally used as a temporary condition. If you mean someone is generally fearful or timid, Spanish would usually use another adjective, such as:

• Mi amigo es miedoso. = My friend is fearful / easily scared.
• Mi amigo es tímido. = My friend is shy.

So for the sentence you were given, está is the correct choice.

To make it plural, both the noun phrase and the verb/adjective must change:

• Mis amigos están asustados. = My friends are scared.

Changes:

• mi → mis
• amigo → amigos
• está → están
• asustado → asustados

If the group is all female:

• Mis amigas están asustadas.

Yes, but Mi amigo está asustado is the most neutral and natural order.

Spanish sometimes allows different word orders for emphasis, for example:

• Está asustado mi amigo.

This can sound more marked or literary, or it may emphasize the condition. But for everyday learning and speaking, stick with:

• Mi amigo está asustado.

That is the standard word order: subject + verb + adjective.

Está is pronounced roughly eh-STA, with the stress on the second syllable.

The accent mark tells you where the stress goes:

• es-TÁ

It also helps distinguish it in writing from other similar-looking forms. In Spanish, written accents are important because they can change pronunciation and sometimes meaning.

Usually asustado most directly matches scared or frightened.

Its strength depends on context. It does not automatically mean terrified. If you want something stronger, Spanish might use:

• aterrado = terrified
• muerto de miedo = scared to death / extremely scared

So asustado is a very normal, common word for someone who is scared.

Traditional Spanish usually requires you to choose a gendered form:

• Mi amigo está asustado.
• Mi amiga está asustada.

In real-life conversation, speakers normally use the form that matches the person they are talking about.

If you are speaking generally and want to avoid specifying sex, you may need to rephrase, depending on context. But in standard beginner Spanish, you usually choose either amigo/asustado or amiga/asustada.