Learn Hardcore Spanish (Latin America): Hoy el mar está muy tranquilo.

El mar es tranquilo.
→ That would sound more like “The sea (in general) is calm”, describing it as a usual or characteristic quality (which is less common unless you’re talking about a specific bay or area that is always calm).

So here está is used because the calmness is a temporary state today.

Why does está have an accent mark?

The accent in está serves two purposes:

Stress position
- Without the accent, esta would be stressed on the second-to-last syllable: ES-ta.
- With the accent, está is stressed on the last syllable: es-TÁ.
  That’s the correct stress pattern for this verb form.
Distinguishing words
- está = he/she/it is, you (usted) are (from estar)
- esta = this (feminine demonstrative adjective: esta casa, esta playa)

So the accent shows both correct pronunciation and that this is the verb form of estar, not the demonstrative esta.

Why is it el mar and tranquilo (masculine), if I’ve sometimes seen la mar?

In modern everyday Spanish, especially in Latin America:

mar is normally masculine: el mar, un mar, el mar tranquilo.
The adjective agrees with that: tranquilo (masculine singular).

You may occasionally see or hear la mar, but:

It’s archaic, poetic, or literary, more common in older texts or in some dialects in Spain.
In everyday Latin American speech, el mar (masculine) is overwhelmingly the standard form.

So for Latin American Spanish learners, treat mar as masculine and match adjectives accordingly: el mar está tranquilo.

Can I change the word order, like El mar está muy tranquilo hoy? Does it change the meaning?

Yes, Spanish allows several natural word orders here, all correct and with essentially the same basic meaning:

Hoy el mar está muy tranquilo. (original)
El mar hoy está muy tranquilo.
El mar está muy tranquilo hoy.

Differences are very subtle and mostly about what you’re highlighting:

Starting with Hoy puts a little more emphasis on today.
Putting hoy at the end (…muy tranquilo hoy) can sound a bit like an afterthought: “It’s very calm…today.”
El mar hoy está muy tranquilo can slightly emphasize the subject (el mar) first and then specify that today that’s the case.

All of them are perfectly natural in everyday speech.

Can I drop the article and just say Hoy mar está muy tranquilo?

No, that would be wrong in standard Spanish.

With singular countable nouns like mar (the sea, considered as a specific thing), you almost always need a definite article:

✅ Hoy el mar está muy tranquilo.
❌ Hoy mar está muy tranquilo.

Spanish generally uses the definite article more often than English, especially with things like:

El mar, el océano, el sol, la luna, el cuerpo, la cabeza, etc.

So when you mean “the sea”, say el mar.

Could I just say Hoy el mar está tranquilo without muy? What’s the difference?

Yes, you can:

Hoy el mar está tranquilo.
→ The sea is calm today.
Hoy el mar está muy tranquilo.
→ The sea is very calm today.

muy intensifies the adjective tranquilo:

Without muy, it’s a neutral description: it’s calm, not rough.
With muy, you’re emphasizing that it’s especially calm — smoother, quieter than usual.

Both are common; which one you choose depends on how strong you want the idea of calmness to be.

Does tranquilo only mean “calm” for the sea, or can it describe people and other things too?

Tranquilo is quite versatile in Spanish. It doesn’t only apply to the sea.

Some common uses:

People (mood or personality)
- Juan está tranquilo. → Juan is calm / relaxed (right now).
- Juan es tranquilo. → Juan is a calm / laid-back person (in general).
Places or situations
- La calle está muy tranquila. → The street is very quiet.
- Fue un día tranquilo. → It was a quiet / uneventful day.
Reassuring someone
- ¡Tranquilo! / ¡Tranquila! → “Relax,” “Don’t worry,” “Take it easy.”

With el mar, tranquilo can convey no waves, not rough, and also peaceful, soothing atmosphere.

Are there regional differences in how people say “today,” like hoy, hoy día, or hoy en día?

Yes, there are some variations, but they’re not interchangeable in every context:

hoy = today (literal, specific day)
- Hoy el mar está muy tranquilo. → today the sea is calm.
hoy día (more common in parts of Latin America)
Often means “nowadays / these days”, not “today only”:
- Hoy día la tecnología avanza muy rápido. → Nowadays, technology advances very fast.
hoy en día (very common generally)
Also usually means “nowadays / in the present era”:
- Hoy en día es fácil viajar. → Nowadays it is easy to travel.

In your sentence, you’re talking about a particular day, so hoy is the natural and correct choice. Hoy día el mar está muy tranquilo would sound more like “These days the sea is very calm,” which is a different meaning.

How would this sentence change if I talk about several seas, or the ocean in general?

For plural “seas”:

Hoy los mares están muy tranquilos.
→ Today the seas are very calm.

Changes:

el mar → los mares (plural of mar)
está → están (third person plural of estar)
tranquilo → tranquilos (plural adjective)

For the ocean (singular):

Hoy el océano está muy tranquilo.
Same structure as the original, just with océano instead of mar.

Agreement rules stay the same: article, noun, verb, and adjective must all match in number (singular/plural) and gender.

How do you pronounce “Hoy el mar está muy tranquilo” naturally in Latin American Spanish?

Key points:

hoy → the h is silent; sounds like [oi], similar to “oy” in English “boy”.
el mar → clear r at the end of mar, a single tap [ɾ], not a long rolled rr.
está → es-TÁ, stress on the last syllable because of the accent.
muy → sounds like [mui], similar to “moo-ee” run together.
tranquilo → trankílo
- qu before i = k sound (no “kw”): tran-KEE-lo.
- ll is usually pronounced like a “y” in much of Latin America: tran-KI-yo or tran-KI-jo, depending on region.

Rhythmically, you’d say it in a smooth flow, linking words:

Hoyel mar está muy tranquilo.

Natural stress by word:

HOY el MAR es-TÁ MUY tran-QUÍ-lo.