Demà anirem en bicicleta al parc si no plou.

Demà means tomorrow, and Catalan often puts time expressions near the beginning of the sentence, just like English can do in Tomorrow we’ll go....

So:

• Demà anirem... = Tomorrow we’ll go...

This is very natural, but it is not the only possible order. You could also say:

• Anirem demà en bicicleta al parc si no plou.

That said, starting with demà is very common when you want to set the time clearly from the start.

Anirem is the future tense of the verb anar (to go) for nosaltres (we).

So:

• anar = to go
• anirem = we will go

A few future forms of anar are:

• aniré = I will go
• aniràs = you will go
• anirà = he/she/it will go
• anirem = we will go
• anireu = you all will go
• aniran = they will go

In this sentence, anirem means we will go.

En bicicleta means by bike or on a bicycle.

In Catalan, en is commonly used to talk about the means of transport:

• en cotxe = by car
• en tren = by train
• en avió = by plane
• en bicicleta = by bicycle

So:

• anirem en bicicleta = we’ll go by bike

This is one of those expressions you should learn as a set phrase.

Al is a contraction of:

• a = to
• el = the

So:

• a + el = al

That means:

• al parc = to the park

This is exactly like similar contractions in some other languages. You use al because parc is masculine singular here: el parc.

Compare:

• al parc = to the park
• a la platja = to the beach
• als nens = to the children
• a l’escola = to the school

Si no plou means if it doesn’t rain.

It introduces a condition:

• si = if
• no = not
• plou = it rains / it is raining

So the whole sentence means that going to the park depends on the weather.

This structure is very common in Catalan:

• Si fa bon temps, sortirem. = If the weather is nice, we’ll go out.
• Si no tens temps, ho faré jo. = If you don’t have time, I’ll do it.

After si when talking about a real future condition, Catalan normally uses the present tense, not the future.

So Catalan says:

• si no plou = literally if it doesn’t rain / if it isn’t raining

Even though in English we are talking about the future, English also usually says:

• If it doesn’t rain, we’ll go...

—not If it won’t rain...

So this is actually quite similar in both languages.

Plou comes from ploure, which means to rain.

Weather verbs like this are usually used without a normal personal subject, just as in English we say it rains, where it does not refer to anything real.

So:

• plou = it rains / it is raining
• no plou = it isn’t raining

Other weather expressions in Catalan include:

• fa sol = it’s sunny
• fa vent = it’s windy
• neva = it snows

Yes, here it is two words:

• si no = if not / if ... not

In your sentence:

• si no plou = if it doesn’t rain

This is different from sinó, written as one word, which usually means but rather or except.

Compare:

• Si no plou, anirem al parc. = If it doesn’t rain, we’ll go to the park.
• No anirem al parc, sinó a la platja. = We won’t go to the park, but rather to the beach.

This distinction is very important in writing.

Yes, absolutely. That is a very natural alternative.

Catalan allows some flexibility in word order, especially with time expressions and conditional clauses.

Both are correct:

• Demà anirem en bicicleta al parc si no plou.
• Si no plou, demà anirem en bicicleta al parc.

The difference is mainly in emphasis:

• Starting with Demà highlights when
• Starting with Si no plou highlights the condition

Usually, if the si clause comes after the main clause, Catalan often does not use a comma:

• Demà anirem en bicicleta al parc si no plou.

If the conditional clause comes first, a comma is normally used:

• Si no plou, demà anirem en bicicleta al parc.

So the punctuation pattern is very similar to English.

Yes, in context it often can.

Literally, anirem en bicicleta is we will go by bicycle, but in natural English that may be translated as:

• we’ll go by bike
• we’ll ride our bikes
• we’ll cycle

The best English translation depends on the context, but the Catalan structure itself is straightforward: it expresses the means of transport.

The sentence is already completely natural. In everyday speech, pronunciation may be a bit smoother or faster, but the wording itself is standard and common.

A speaker might also choose a slightly different wording, such as:

• Demà anirem amb bicicleta al parc si no plou.

In many contexts, en bicicleta is the standard expression, but amb bicicleta may also be heard in speech depending on region and speaker.

Still, for a learner, en bicicleta is the safest and most standard choice to remember.

A simple approximate pronunciation is:

• deh-MA ah-nee-REM em bee-see-KLEH-tuh uhl PARK see no PLOH-oo

A few helpful notes:

• Demà has stress on the last syllable: de-MÀ
• anirem has stress on the last syllable: ani-REM
• bicicleta has stress on cle: bici-CLE-ta
• plou sounds roughly like plo-oo, as one syllable with a glide

If you want, you can also think of the rhythm in chunks:

• Demà / anirem / en bicicleta / al parc / si no plou

Yes, if the time is already clear from context.

For example:

• Anirem en bicicleta al parc si no plou. = We’ll go to the park by bike if it doesn’t rain.

Without demà, the sentence still works perfectly, but it no longer specifically says tomorrow. So demà adds clear time information.

Catalan often leaves out subject pronouns because the verb ending already shows who the subject is.

Here:

• anirem already tells you the subject is nosaltres (we)

So:

• Demà anirem... = Tomorrow we will go...
• Demà nosaltres anirem... = also possible, but more emphatic

You would usually add nosaltres only if you want contrast or emphasis.