Aquest arbre fa molta ombra al pati a l'estiu.

Aquest means this.

So aquest arbre = this tree.

Catalan demonstratives agree with the gender and number of the noun:

• aquest = this, masculine singular
• aquesta = this, feminine singular
• aquests = these, masculine plural
• aquestes = these, feminine plural

Since arbre is a masculine singular noun, aquest is the correct form.

In Catalan, you normally do not use the definite article before a demonstrative in this kind of phrase.

So:

• aquest arbre = this tree

Not:

• el aquest arbre

This is similar to English, where you say this tree, not the this tree.

Literally, fa molta ombra means makes a lot of shade.

Catalan often uses fer (to do / to make) in expressions where English uses a different verb. Here:

• fer ombra = to provide shade / to cast shade

So Aquest arbre fa molta ombra means:

• This tree provides a lot of shade
• This tree casts a lot of shade

All of those are natural translations depending on context.

Fa is the third person singular form of fer (to do / to make).

The subject is aquest arbre (this tree), which is singular, so the verb must also be singular:

• Aquest arbre fa... = This tree makes/does...

Some forms of fer:

• faig = I do/make
• fas = you do/make
• fa = he/she/it does/makes

Because tree is treated like it in English, Catalan uses fa.

Because ombra is a feminine singular noun, the word meaning a lot of / much must agree with it.

• molt = masculine singular
• molta = feminine singular
• molts = masculine plural
• moltes = feminine plural

So:

• molta ombra = a lot of shade

This agreement is very important in Catalan.

Here ombra is being used as an uncountable noun, like shade in English.

So:

• molta ombra = a lot of shade

If you said ombres, that would mean shadows as separate countable things. That is a different idea.

In this sentence, the meaning is general shade created by the tree, so ombra in the singular is the natural choice.

Al means to the or in the, depending on context.

It is a contraction of:

• a + el = al

So:

• al pati = in the patio / in the yard / to the patio, depending on the sentence

In this sentence, al pati means something like:

• in the patio
• in the yard
• over the patio area

Catalan normally contracts a + el into al.

It is related, but not always exactly the same.

Pati usually means:

• yard
• courtyard
• patio
• sometimes an outdoor enclosed area

The exact translation depends on context. In this sentence, pati could be translated as yard or patio, depending on what kind of space is being described.

Even though English has the word patio, you should not assume pati always matches it perfectly.

Because the preposition a combines with the article l' before a vowel.

Here:

• estiu = summer
• the definite article before a masculine singular noun beginning with a vowel is l'
• so a + l'estiu becomes a l'estiu

This means:

• in the summer
• during the summer

The apostrophe appears because the article el is reduced before a vowel:

• el estiu does not occur
• l'estiu is correct

Catalan usually uses a preposition plus article for seasons in expressions like this.

So:

• a l'estiu = in summer / in the summer

This is very natural Catalan. English can sometimes omit the article and just say in summer, but Catalan generally uses a l' here.

You may also hear similar time expressions such as:

• a l'hivern = in winter
• a la primavera = in spring
• a la tardor = in autumn

The word order is quite natural in Catalan:

• Aquest arbre = subject
• fa = verb
• molta ombra = direct object / main idea after the verb
• al pati = place
• a l'estiu = time

So the structure is roughly: Subject + verb + thing affected + place + time

English often works similarly:

• This tree gives a lot of shade in the yard in summer.

Catalan is fairly flexible, though. For emphasis, you could move parts around, for example:

• A l'estiu, aquest arbre fa molta ombra al pati.

That puts more focus on in summer.

Yes, dona molta ombra can also be understood and can sound natural in some contexts, meaning gives a lot of shade.

However, fer ombra is a very common and idiomatic expression in Catalan. So in this sentence, fa molta ombra is an excellent standard choice.

It is often best to learn fer ombra as a set expression.

A rough pronunciation guide for an English speaker is:

ah-KESHT AR-bruh fah MOL-tuh OM-bruh ahl PA-tee ah ləs-TEE-ew

A few useful notes:

• aquest is often pronounced roughly like uh-KEST or ah-KESHT, depending on accent
• arbre has two r sounds close together, which can be tricky
• ombra has an open o sound in many accents
• l'estiu sounds like ləs-TEE-ew or similar

Pronunciation varies across Catalan-speaking regions, so exact sound details may differ.

It usually describes a general characteristic or habitual situation:

• This tree gives a lot of shade in the yard in summer.

So it is not necessarily about this exact moment. It means that, in general, during summer, this tree creates a lot of shade there.

Catalan uses the present tense for this kind of general truth, just like English often does.