A casa, la meva germana copia els deures del meu quadern perquè ahir no va venir a classe.

A casa means at home. It is a very common fixed expression in Catalan.

A few useful points:

• a = at / to
• casa = house / home
• A casa usually means at home, not necessarily to the house
• Catalan often uses casa without an article in this expression

So:

• Sóc a casa = I’m at home
• Arribo a casa = I arrive home

In your sentence, A casa sets the scene: this is happening at home.

In Catalan, possessives are very often used together with the definite article:

• el meu pare = my father
• la meva germana = my sister
• els meus amics = my friends

So la meva germana is the normal way to say my sister.

English does not use an article here, but Catalan usually does.

A small note: With some family words in certain contexts, especially in direct address or some very close kinship uses, the article may be dropped. But for normal statements, la meva germana is exactly what learners should expect.

Catalan often leaves out subject pronouns when they are not needed.

So instead of saying:

• Ella copia els deures...

it is very natural to say:

• La meva germana copia els deures...

or even just:

• Copia els deures...

if the subject is already clear from context.

That is because the verb form often gives enough information. Here, copia is the he/she/it form, and the noun phrase la meva germana already tells us who is doing the action.

Copia is the present tense of copiar = to copy.

Here it means copies / is copying, depending on context.

Catalan uses the simple present in many cases where English might use either:

• she copies
• she is copying

So la meva germana copia can mean:

• my sister copies
• my sister is copying

In this sentence, the meaning is probably something like is copying, but the Catalan form is just the normal present tense.

Because Catalan treats this idea differently from English.

• els deures literally means the assignments / the exercises / the homework tasks
• English usually uses uncountable homework
• Catalan normally uses the plural deures

So:

• Tinc molts deures = I have a lot of homework
• Fa els deures = He/She does homework

This is a very common difference between Catalan and English.

del is a contraction of:

• de
  • el = del

So:

• del meu quadern = from my notebook

Breakdown:

• de = of / from
• el meu quadern = my notebook
• del meu quadern = from my notebook or sometimes of my notebook, depending on context

In this sentence, the natural meaning is that she is copying the homework from my notebook.

Yes. Quadern means notebook or exercise book.

So:

• el meu quadern = my notebook

Depending on context, a Catalan learner may also see related words like:

• llibre = book
• llibreta = small notebook / notepad
• quadern = notebook / exercise book

Here, quadern makes sense because homework or class notes are often written there.

Perquè with an accent means because.

This is an important word to learn, because Catalan distinguishes several similar-looking forms:

• perquè = because
• per què = why / for what
• per que = less common combination in other structures
• el perquè = the reason why

In your sentence:

• ...perquè ahir no va venir a classe = ...because yesterday she didn’t come to class

So here perquè introduces the reason.

Yes, and this is one of the most important things to learn in Catalan grammar.

Va venir is a very common past tense form called the periphrastic past.

Structure:

• va
  • infinitive

So:

• va venir = came
• va copiar = copied
• va arribar = arrived

Even though va by itself can mean goes or went as a form of anar, in this structure it functions as part of a past tense.

So:

• ahir no va venir = yesterday she didn’t come

This is completely normal Catalan.

In Catalan, no usually goes directly before the verb.

So:

• no ve = she doesn’t come
• no copia = she doesn’t copy
• no va venir = she didn’t come

That is why the sentence says:

• ahir no va venir a classe

This is the standard position for negation.

Here a classe means to class or to school/class in a general sense.

Catalan often leaves out the article in this kind of expression when talking about attending class as an activity or institution.

So:

• venir a classe = to come to class
• anar a classe = to go to class

If you said a la classe, that would more likely point to a specific physical classroom or a specific class in a more concrete way.

In this sentence, the general meaning is simply that she did not attend class yesterday, so a classe is the natural choice.

Ahir means yesterday, and Catalan allows fairly flexible placement for time expressions.

Here:

• perquè ahir no va venir a classe

means:

• because yesterday she didn’t come to class

Putting ahir before the verb is very natural. You could also hear other word orders in Catalan depending on emphasis, but this one is straightforward and common.

The sentence is built like this:

• A casa, = place/topic setting
• la meva germana = subject
• copia = verb
• els deures = direct object
• del meu quadern = source/complement
• perquè ahir no va venir a classe = reason clause

So the overall structure is roughly:

At home, my sister copies the homework from my notebook because yesterday she didn’t come to class.

Catalan often follows a familiar subject + verb + object pattern, but it can also move time and place expressions around quite naturally.

Catalan possessives agree with the noun they describe, not with the owner.

Here:

• germana is feminine singular, so you use meva
• quadern is masculine singular, so you use meu

That is why you get:

• la meva germana
• el meu quadern

Other forms are:

• el meu = my, masculine singular
• la meva = my, feminine singular
• els meus = my, masculine plural
• les meves = my, feminine plural

Yes. That is a good way to understand it.

The phrase suggests that the homework is being copied from what is written in my notebook. In natural English, depending on context, you might translate it as:

• copies the homework from my notebook
• copies the homework out of my notebook
• copies my homework from my notebook

The exact English wording can vary, but the Catalan idea is clear: the notebook is the source she is copying from.