Como la marea estaba alta, preferimos dejar la tumbona más lejos del agua y cerrar bien la sombrilla.

In this sentence, como is being used as a conjunction, not as an interrogative or adverb.

At the start of a sentence, como can mean since / because:

• Como la marea estaba alta... = Since/Because the tide was high...

This use is very common in Spanish, especially when the speaker gives the reason first.

Compare:

• ¿Cómo estás? = How are you?
• Como estaba cansado, me fui. = Because I was tired, I left.

So the meaning depends on the structure and position in the sentence.

Estaba is the imperfect tense of estar, and it is used here to describe a background condition: the tide was high at that time.

Spanish often uses the imperfect for:

• background descriptions
• ongoing states
• situations already in progress

Here, the high tide is the circumstance that explains the action.

• Como la marea estaba alta... = the tide was high at that moment / during that situation

If you said estuvo alta, it would sound more like a completed event viewed as a whole, which is less natural here because the sentence is setting the scene rather than narrating a finished event.

Preferimos is the preterite, and it shows a specific decision or action made at that moment:

• preferimos dejar... y cerrar... = we decided/preferred to leave... and close...

The preterite presents it as a completed choice.

If you used preferíamos, it would sound more like:

• a habitual preference
• an ongoing mental state
• a background idea rather than a specific decision

So in this sentence, preferimos fits because the speakers made a concrete choice in response to the high tide.

Spanish often omits subject pronouns because the verb ending already shows who the subject is.

• preferimos clearly means we prefer / we preferred

So nosotros is unnecessary unless you want emphasis or contrast.

Compare:

• Preferimos dejar la tumbona... = normal, natural
• Nosotros preferimos dejar la tumbona... = more emphatic, as in we preferred, maybe contrasting with someone else

This is very common in Spanish.

Marea alta means high tide.

The adjective alta agrees with marea, which is a feminine noun:

• la marea
• therefore alta, not alto

This is just normal adjective agreement in Spanish:

• el mar alto would be masculine
• la marea alta is feminine

So la marea estaba alta literally means the tide was high.

Yes, tumbona is very common in Spain. It usually means a sun lounger, deck chair, or reclining beach chair.

It refers to the kind of chair you lie back on at the beach or pool.

In other Spanish-speaking regions, other words may be used, depending on the country. But for Spain, tumbona is a very natural choice.

Here, dejar means to leave / put / place something somewhere.

So:

• dejar la tumbona más lejos del agua = to leave / place the sun lounger farther from the water

This structure is common:

• dejar + object + place/adverbial phrase

Examples:

• Dejé la mochila en el coche. = I left the backpack in the car.
• Dejaron las toallas cerca de la sombrilla. = They left the towels near the parasol.

In your sentence, the speakers are moving or positioning the lounger at a greater distance from the water.

Lejos del agua means far from the water.

Más lejos del agua means farther from the water.

The más adds a comparative idea: they chose a position at a greater distance than before, or greater than some other possible position.

So:

• lejos del agua = far from the water
• más lejos del agua = farther from the water

This makes sense in context because the tide is high, so they move the lounger to a safer spot.

Because de + el contracts to del in Spanish.

So:

• de + el agua → del agua

This contraction is mandatory.

The only common exception is when el is part of a proper name, for example:

• de El Escorial

But in normal noun phrases, you use the contraction:

• del agua
• del coche
• del hotel

Because preferir can be followed by an infinitive to say what someone prefers to do.

Here the verb governs two coordinated infinitives:

• preferimos dejar la tumbona... y cerrar bien la sombrilla

That means:

• we preferred to leave the lounger... and to close the parasol properly

This is completely normal in Spanish. The second infinitive shares the same subject and main verb.

Similar examples:

• Prefiero comer y descansar. = I prefer to eat and rest.
• Preferimos esperar y volver más tarde. = We preferred to wait and come back later.

Cerrar bien means to close properly / securely / tightly.

The adverb bien adds the idea that it was done thoroughly, not just casually.

In context, with wind or changing beach conditions, cerrar bien la sombrilla suggests making sure the parasol is fully and properly closed so it does not move or blow away.

Compare:

• cerrar la sombrilla = close the parasol
• cerrar bien la sombrilla = close it properly / make sure it’s well closed

Sombrilla is usually a sunshade, parasol, or beach umbrella. Its main purpose is to protect from the sun.

Paraguas means umbrella, usually for rain.

So at the beach, sombrilla is the natural word.

Related idea:

• sombra = shade
• sombrilla comes from that idea of providing shade

Yes. You could say:

• Preferimos dejar la tumbona más lejos del agua y cerrar bien la sombrilla porque la marea estaba alta.

This is also correct.

The difference is mostly one of emphasis and flow:

• Como la marea estaba alta, ... puts the reason first
• ..., porque la marea estaba alta gives the action first and the explanation after

Starting with como is very common when the speaker wants to present the cause as the frame for everything that follows.