Learn Hardcore Spanish (Latin America): Mi amigo prefiere estudiar física porque le gustan los planetas. - My friend prefers to study physics because he likes planets.

Los planetas is plural → the verb must be plural: gustan.
If it were singular, you’d say:
- Le gusta el planeta. = He/She likes the planet.
- Le gustan los planetas. = He/She likes the planets.

Le refers to the person (to him/her), but gusta / gustan agrees with what is liked (singular/plural).

What does “le” mean in “porque le gustan los planetas”?

Le is an indirect object pronoun meaning “to him” / “to her” here.

Literally, le gustan los planetas is like saying:
“The planets are pleasing to him/her.”

Le = to him / to her (refers to mi amigo)
gustan = are pleasing
los planetas = the planets

You could make it extra-clear (though not necessary) by saying:

A mi amigo le gustan los planetas. = My friend likes planets.

Why do we say “los planetas” with “los”, when in English we just say “likes planets” (no “the”)?

Spanish very often uses the definite article (el / la / los / las) when talking about things in general:

Le gustan los perros. = He/She likes dogs (dogs in general).
No como la carne. = I don’t eat meat (meat in general).

So le gustan los planetas is the natural way to say “he likes planets” in general.
Leaving out los (le gustan planetas) is not correct here.

Why is “porque” written as one word and not “por qué”?

Porque and por qué are different:

Porque (one word) = because
- Estudio español porque me gusta. = I study Spanish because I like it.
Por qué (two words, accent) = why, usually in questions
- ¿Por qué estudias español? = Why do you study Spanish?

In the sentence “Mi amigo prefiere estudiar física porque le gustan los planetas”, it means “because”, so it must be porque.

Why is it “prefiere estudiar física” and not “prefiere estudia física”?

In Spanish, after many verbs of preference, desire, etc., you use the infinitive (the base form), not a conjugated verb.

Preferir + infinitive
- Mi amigo prefiere estudiar física. = My friend prefers to study physics.
- Not: prefiere estudia física (incorrect).

Other similar patterns:

Quiero aprender español. = I want to learn Spanish.
Ella necesita dormir. = She needs to sleep.

Why don’t we say “prefiere a estudiar física” with an “a” before “estudiar”?

In Spanish, you do not put a before an infinitive when it is a direct object of a verb like “preferir”.

✅ Prefiere estudiar física.
❌ Prefiere a estudiar física.

You do see a + infinitive in other structures, like:

Antes de estudiar física… = Before studying physics…
Empieza a estudiar física. = He/She starts to study physics.

But specifically after preferir, the pattern is just preferir + infinitive.

Should it be “estudiar física” or “estudiar la física”? When do we use “la” with school subjects?

Both are possible, but in this kind of sentence without “la” is very common and sounds natural:

Mi amigo prefiere estudiar física.

In general:

After verbs like estudiar, enseñar, aprender, the article can be dropped:
- Estudio matemáticas. / Estudio las matemáticas.
- Quiero aprender inglés. / el inglés.

Using la física can sound a bit more like talking about the discipline as a subject or field (e.g., “Physics as a science”), but in everyday speech, especially in Latin America, “estudiar física” is very normal.

If my friend is a girl, do I say “mi amiga” instead of “mi amigo”?

Yes.

Mi amigo = my (male) friend
Mi amiga = my (female) friend

The rest of the sentence stays the same:

Mi amiga prefiere estudiar física porque le gustan los planetas.

Le still works for both genders; it can mean to him or to her.

Why don’t we say “Él mi amigo prefiere…” or add “él” before “prefiere”?

In Spanish, subject pronouns (yo, tú, él, ella, etc.) are often omitted, because the verb ending already shows who the subject is.

Here, the subject mi amigo is explicitly given, so we don’t need él:

✅ Mi amigo prefiere estudiar física.
❌ Él mi amigo prefiere estudiar física. (sounds wrong / redundant)

You could say:

Él prefiere estudiar física… (using él instead of mi amigo), but not both together that way.

What tense is “prefiere”, and does it mean “prefers” in general or “is preferring right now”?

Prefiere is present indicative, 3rd person singular of preferir.

In Spanish, the simple present is used both for:

General preferences / habits:
- Mi amigo prefiere estudiar física. = My friend prefers to study physics (in general).
And for things happening around now (depending on context).

Spanish does not use a continuous form (“is preferring” doesn’t even sound natural in English either), so prefiere is the correct form for a general preference.

Why does “física” have an accent mark?

Física follows Spanish stress rules:

It has three syllables: FÍ-si-ca.
The stress falls on the third-from-last (antepenultimate) syllable: FÍ.
In Spanish, words stressed on the antepenultimate syllable must have a written accent.

So we write física, not fisica.

Also, física here is a noun meaning physics (the subject). It’s grammatically feminine, which is why you’d use la física if you added an article.