Puella misera in cubiculo sedet, quia amica eius abest.

Because misera agrees with puella.

• puella is feminine, singular, nominative.
• Adjectives in Latin must match the nouns they describe in gender, number, and case.
• So the adjective miser, misera, miserum becomes misera to match puella.

So puella misera means the unhappy girl or the miserable girl.

Puella is nominative singular.

In Latin, the subject of a finite verb is usually in the nominative case. Here the verb is sedet (sits / is sitting), so puella is the one doing the action.

The ending -a in a first-declension noun like puella often marks the nominative singular.

Because in with the ablative usually means in or on in the sense of location.

Here, in cubiculo means in the room / bedroom, describing where the girl is sitting.

A useful rule is:

• in + ablative = location (in, on)
• in + accusative = motion into (into, onto)

So:

• in cubiculo sedet = she sits in the room
• but in cubiculum intrat would mean she enters into the room

Cubiculum is a second-declension neuter noun. Its basic form is cubiculum.

In the ablative singular, second-declension nouns usually end in -o, so:

• nominative: cubiculum
• ablative: cubiculo

Since in here takes the ablative for location, we get in cubiculo.

Sedet is:

• 3rd person singular
• present tense
• active voice
• indicative mood

It comes from sedeo, sedere = to sit.

So sedet means she sits or she is sitting.

Latin often does not need an expressed subject pronoun like she, because the verb ending already tells you the person and number.

Latin does not have definite or indefinite articles like English the and a/an.

So puella can mean:

• girl
• a girl
• the girl

The context tells you which is best in translation.

The same is true for amica and cubiculo.

Latin word order is more flexible than English word order because Latin uses endings to show grammatical relationships.

So in Puella misera in cubiculo sedet, we know:

• puella is the subject because it is nominative
• misera describes puella
• in cubiculo is a prepositional phrase
• sedet is the verb

Because those relationships are clear from the forms, Latin can move words around more freely for style or emphasis.

This sentence has a fairly natural Latin order, but other orders could still make sense.

Quia means because.

It introduces a clause giving the reason for the main statement:

• main clause: Puella misera in cubiculo sedet
• reason clause: quia amica eius abest

So the sentence means that the girl is unhappy and sitting in her room because her friend is away.

This is a very common and important question.

• eius means his / her / its and usually refers to someone else, not the subject of the clause it is in.
• suus, sua, suum is a reflexive possessive and refers back to the subject of its own clause.

In the clause quia amica eius abest, the subject is amica (friend). So:

• amica sua would mean her own friend, where sua refers back to amica herself
• that does not express the girl's friend

But eius can refer back to puella from the main clause:

• amica eius = her friend = the girl's friend

So eius is the correct choice here.

Eius is the genitive singular form of is, ea, id, a demonstrative/pronominal word often translated as he, she, it, that depending on context.

As a genitive, eius means:

• of him
• of her
• of it
• and very often simply his / her / its

Here it means her, referring to puella.

So amica eius literally means the friend of her, which in natural English becomes her friend.

Abest means is away or is absent.

It comes from absum, abesse, which is a compound of:

• ab = away from
• sum = I am

So literally it has the idea of being away.

Grammatically, abest is:

• 3rd person singular
• present indicative

So amica eius abest means her friend is away / absent.

Yes. Latin could also say eius amica.

Both amica eius and eius amica are possible. Word order in Latin is flexible, and the choice can depend on rhythm, emphasis, or style.

A learner should mainly remember that:

• the form eius is correct here
• its position is somewhat flexible

Because this sentence gives a straightforward, factual reason:

• the girl is unhappy
• because her friend is away

Latin commonly uses quia with the indicative when the speaker presents the reason as a fact. So abest is completely normal here.

At an elementary level, the simplest rule is:

• quia + indicative = because, giving a real reason

Because amica is in the nominative singular, and abest is 3rd person singular.

They match:

• amica = singular subject
• abest = singular verb

So amica is the one who is away.

Meanwhile eius is in the genitive and cannot be the subject.

Usually cubiculum means bedroom or sleeping room, though in some contexts it can be translated more generally as room.

So in cubiculo could be understood as:

• in the bedroom
• or more loosely in her room

The exact English wording depends on the context and the translation style.