Learn Hardcore Spanish (Latin America): En el curso en línea hay foros donde los estudiantes hacen preguntas. - In the online course there are forums where students ask questions.

En el curso en línea = In the (specific) online course
- Maybe one that the teacher and students already know about.
En un curso en línea = In an online course (any course, not a particular one).

So the original sentence assumes speaker and listener have a specific course in mind.

What does en línea mean literally, and is it the usual way to say online in Latin American Spanish?

Literally, en línea means in line, but in modern usage it means online (connected to the internet).

In Latin American Spanish, common ways to say online include:

en línea – very common and neutral
en internet / por internet – on/over the internet
online – the English word, also used, especially in tech/marketing contexts

In this sentence, curso en línea is a very normal, natural way to say online course in Latin America.

Why do we use hay here instead of son or están?

Hay is used to talk about the existence of something (there is/there are).

Hay foros = There are forums (they exist in that course).

Compare:

En el curso en línea hay foros.
Focus: the fact that forums exist in that course.
Los foros están en el curso en línea.
Focus: the location of specific forums (where they are).
Here you need los foros (definite), not just foros.
Los foros son interesantes.
Focus: a description (the forums are interesting).

So hay is the correct choice because the sentence is introducing the existence of forums in the course.

Why is there no article before foros (why not hay unos foros or hay los foros)?

After hay, Spanish normally uses a bare noun (no article) when the thing is being introduced in a general, non-specific way.

Hay foros = There are forums (some forums, in general).
Hay unos foros = There are some forums (a bit more specific, often with a nuance like “a few forums”).
Hay los foros – this is incorrect in Spanish. You don’t combine hay with a definite article (el, la, los, las).

So hay foros is the natural, general way to say there are forums.

What is the function of donde in foros donde los estudiantes hacen preguntas? Could I say en los que instead?

Here, donde is a relative adverb meaning where. It links foros to the clause that describes them:

foros donde los estudiantes hacen preguntas
= forums where the students ask questions

You can say:

foros en los que los estudiantes hacen preguntas

This is also grammatically correct and common. The difference:

donde – a bit more direct and very natural when talking about places (forums, cities, rooms, websites, etc.).
en los que – slightly more formal/explicit, but very normal.

So both are fine; donde is just the simpler option.

Why is it los estudiantes and not just estudiantes?

Spanish often uses a definite article with plural nouns when English would drop it.

los estudiantes can mean either:
- the students (of this course) – specific group, or
- students in general – a generic group, depending on context.

Compare:

Los estudiantes hacen preguntas.
Natural, standard Spanish.
Estudiantes hacen preguntas.
Possible, but feels incomplete or headline-like (something you might see in a title or bullet point, not in normal spoken language).

So los is used to make the phrase sound complete and natural; it often marks the general category or the specific known group. Context decides which.

Why do we say hacen preguntas instead of simply preguntan?

Both are possible, but they’re used a bit differently.

hacer preguntas = to ask questions (literally to make questions)
- Very common, neutral expression.
- Emphasizes the activity of asking questions.
preguntar = to ask (usually to ask someone something)
- Typically needs an object (what you ask) or an indirect object (who you ask):
  - Los estudiantes preguntan mucho. = The students ask a lot (of questions).
  - Los estudiantes preguntan al profesor. = The students ask the teacher.

In the original sentence, hacen preguntas is a clear, explicit way to say they ask questions without needing to add more information. Los estudiantes preguntan would also be correct, but hacen preguntas is very typical and slightly more explicit.

Why is preguntas plural? Could we say hacen una pregunta?

Yes, you can say hacen una pregunta. The difference is in meaning:

hacen preguntas = they ask questions (in general; it’s something that happens regularly or repeatedly).
hacen una pregunta = they ask a question (one specific question, or each one asks one).

In a general description of what happens in forums, Spanish normally uses the plural:

En los foros, los estudiantes hacen preguntas.
= They ask (various) questions there.

Could the word order be different, like Hay foros en el curso en línea donde…?

Yes, that word order is also correct:

En el curso en línea hay foros donde los estudiantes hacen preguntas.
Hay foros en el curso en línea donde los estudiantes hacen preguntas.

Both mean the same thing. The difference is focus:

Starting with En el curso en línea… emphasizes the course first.
Starting with Hay foros… emphasizes the existence of the forums first.

Grammatically, both are fine.

Is curso masculine because of its ending, and how do I know to use el and not la?

Yes, curso is masculine: el curso.

General tendency:

Many nouns ending in -o are masculine: el libro, el curso, el teléfono.
Many nouns ending in -a are feminine: la casa, la mesa, la pregunta.

But there are exceptions, so you usually learn the noun together with its article:

el curso (the course)
el problema (masculine even though it ends in -a)
la mano (feminine even though it ends in -o)

Here, curso follows the regular -o = masculine pattern, so you use el.

What is the accent mark in línea for, and how is the word pronounced?

The accent mark in línea shows:

Where the stress falls: on the first syllable lí.
That the i and e do not form a single syllable; the word is three syllables: lí-ne-a.

Pronunciation (in simple terms):

lí – like lee in English “leaf”
ne – like neh
a – like the a in “father”

So you say: LÍ-ne-a, not li-NE-a.