Learn Hardcore German: Nach dem Vortrag stelle ich eine kurze Rückfrage, die sich in einem Satz beantworten lässt. - After the talk I ask a short follow‑up question that can be answered in one sentence.

nach den Vortrag – den is accusative masculine (or dative plural), but nach does not use accusative.
nach der Vortrag – der is nominative masculine or dative feminine; Vortrag is not feminine, so this doesn’t fit.

Why does the sentence start with Nach dem Vortrag and then have stelle ich? Could I say Ich stelle nach dem Vortrag … instead?

German main clauses follow the verb-second (V2) rule: the finite verb (here: stelle) must be in second position.

You can put different elements in the first position:

Nach dem Vortrag stelle ich eine kurze Rückfrage …
Ich stelle nach dem Vortrag eine kurze Rückfrage …

Both are correct. In (1), the time phrase Nach dem Vortrag is in the first position, so the verb stelle comes next, and the subject ich follows the verb (inversion). In (2), the subject ich is in first position, so the verb still stays second.

So yes, Ich stelle nach dem Vortrag eine kurze Rückfrage … is perfectly fine; it just emphasizes I more than after the lecture.

Why is it stelle ich eine kurze Rückfrage and not frage ich eine kurze Rückfrage or something like frage ich kurz zurück?

In German, you normally “stellen” a question:

eine Frage stellen = to ask a question
eine Rückfrage stellen = to ask a follow-up question

You do not say eine Frage fragen or eine Rückfrage fragen.

The verb fragen is used differently:

jemanden fragen = to ask someone
- Ich frage dich. = I ask you.
jemanden etwas fragen = to ask someone something
- Ich frage dich etwas. = I ask you something.

So:

ich stelle eine Rückfrage (correct)
ich frage eine Rückfrage (incorrect)

Your variant frage ich kurz zurück is grammatically possible, but:

zurückfragen = to ask back / to ask in return
kurz = briefly

So ich frage kurz zurück means “I briefly ask back,” and it’s more informal and less precise than eine kurze Rückfrage stellen, which clearly refers to a specific follow-up question.

What exactly does Rückfrage mean, and how is it different from just Frage?

Frage = a question, in general.
Rückfrage = a follow-up question / clarification question about something that was just said, written, or presented.

You use Rückfrage when:

you want to clarify a detail
you want to check that you understood something
you are referring back to a previous statement

Example:

Nach deinem Vortrag habe ich noch eine Rückfrage.
= After your talk I still have a follow‑up question (about the talk).

If you say eine Frage, it could be any kind of question; eine Rückfrage implies it is connected to the previous content.

Why is it eine kurze Rückfrage and not eine kurzen Rückfrage?

This is about adjective endings.

Rückfrage = feminine noun (die Rückfrage)
Here it’s in accusative singular (direct object).
With the indefinite article eine
- feminine accusative, the adjective ending is -e:

Pattern:

eine
- feminine accusative noun → adjective takes -e

So:

eine kurze Rückfrage (correct)
eine kurzen Rückfrage (incorrect; -n would be used in other gender/case combinations, but not here)

In die sich in einem Satz beantworten lässt, what does die refer to, and why is it die and not der or das?

die is a relative pronoun that refers back to Rückfrage.

Rückfrage is feminine singular → die Rückfrage.
A relative pronoun must match the gender and number of its noun:
- feminine singular → die

Within the relative clause, die is the subject of the clause:

die (Rückfrage) lässt sich in einem Satz beantworten.

Subjects in German take the nominative, and the feminine nominative singular relative pronoun is die.

So:

die → correct (feminine, nominative, singular, referring to Rückfrage)
der → would be masculine nominative or feminine dative; doesn’t match here.
das → neuter nominative; doesn’t match Rückfrage’s gender.

How does the structure sich … beantworten lässt work? Why not just say something like die man in einem Satz beantwortet?

The structure lassen + sich + Infinitiv is a common way to express a kind of “can be done” / “is possible” meaning, similar to a passive.

Die Rückfrage lässt sich in einem Satz beantworten.
≈ The follow‑up question can be answered in one sentence.

Breakdown:

lässt = 3rd person singular of lassen
sich = reflexive pronoun
beantworten = infinitive (to answer)

Altogether: “The question lets itself be answered in one sentence” → idiomatically: “can be answered in one sentence”.

If you say:

die man in einem Satz beantwortet

that’s not complete as a general statement. You need something like:

die man in einem Satz beantworten kann = that one can answer in one sentence.

So lässt sich beantworten is roughly equivalent in meaning to kann beantwortet werden (can be answered), and it sounds quite natural and somewhat neutral/formal.

Why is beantworten used instead of simply antworten?

Because in German:

beantworten is transitive: it takes a direct object (what is being answered).
antworten is intransitive: you normally answer to someone / to something with a preposition.

Examples:

eine Frage beantworten = to answer a question
auf eine Frage antworten = to answer a question (literally: “to answer to a question”)

In your sentence, die (Rückfrage) is the direct object of answering, so the verb beantworten is the natural choice:

die sich in einem Satz beantworten lässt
= that can be answered in one sentence.

… sich in einem Satz antworten lässt would be ungrammatical.

What does in einem Satz express here, and why not mit einem Satz?

in einem Satz here means “in one sentence / in a single sentence.” It’s about the extent or length of the answer.

in einem Satz beantworten = answer using only one sentence.

If you say mit einem Satz, it sounds more like you are focusing on the means/tool (“with one sentence”) and is not idiomatic in this context. Native speakers use:

in einem Satz (kurz) beantworten
mit einem Satz antworten is unusual; you would almost always say in einem Satz.

So: stick with in einem Satz, which matches English “in a sentence.”

What does lässt mean here exactly? Is it the same lassen as in Ich lasse mein Auto reparieren?

Yes, it’s the same verb lassen, and the structure is very similar.

Ich lasse mein Auto reparieren.
= I have my car repaired / I get my car repaired.
Structure: lassen
- object + infinitive
Die Rückfrage lässt sich in einem Satz beantworten.
= The follow‑up question can be answered in one sentence.
Structure: lassen
- sich
  - infinitive

In (2), lassen doesn’t mean “to cause someone to do something” in a personal sense; instead it expresses that something “allows itself to be done” → can be done.

So lässt here = “is such that it can be …”, functioning like “can be answered”.

Could I instead say die man in einem Satz beantworten kann? Is there any difference in meaning or style?

Yes, you can say:

… eine kurze Rückfrage, die man in einem Satz beantworten kann.

The meaning is essentially the same:

die sich in einem Satz beantworten lässt
die man in einem Satz beantworten kann

Both ≈ “that can be answered in one sentence”.

Nuances:

lässt sich beantworten sounds a bit more impersonal and slightly more formal; common in written German.
man … beantworten kann is very neutral / everyday.

In normal conversation, both are fine. In slightly more formal writing, lässt sich beantworten may be preferred.

Why is the tense stelle ich (present) used, when in English we might say “I will ask” about something in the future?

German often uses the present tense with a future time expression instead of the future tense.

Nach dem Vortrag stelle ich eine kurze Rückfrage.
Literally: “After the talk I ask a short follow‑up question,”
but idiomatically: “I’ll ask a short follow‑up question after the talk.”

Because Nach dem Vortrag clearly places the action in the future, German does not need the future tense.

You could say:

Nach dem Vortrag werde ich eine kurze Rückfrage stellen.

This is also correct, but sounds a bit more explicit/marked, often used to emphasize intention or planning. The simple present is more common and natural here.

Where does the comma before die come from? What’s the rule?

The comma marks the beginning of a relative clause.

Main clause: Nach dem Vortrag stelle ich eine kurze Rückfrage
Relative clause: die sich in einem Satz beantworten lässt

In German, a comma is mandatory before a relative clause introduced by a relative pronoun (der, die, das, welcher, etc.).

So the comma before die follows this rule:

Comma + relative pronoun → start of relative clause.