Learn Hardcore German: In einer Umfrage erklären viele Leute, dass sie nur die Überschrift lesen. - In a survey many people explain that they only read the headline.

In einer Umfrage literally means in a survey – it focuses on the survey as a medium or source of data. It’s like saying: Looking at the survey results, we see that…
Bei einer Umfrage literally means at / during a survey – it focuses more on the situation or occasion when the answers were given.

In practice, In einer Umfrage is very common when reporting findings or results of a survey, which fits this sentence very well.

Why is it In einer Umfrage (dative) and not In eine Umfrage (accusative)?

The preposition in can take either dative or accusative:

Dative = location (where?)
Accusative = direction / movement (where to?)

Here we are talking about where the statements appear (inside a survey), not moving into a survey. So we use dative:

In einer Umfrage – in a survey (location, dative)
In eine Umfrage – into a survey (movement, accusative), e.g. Wir fügen eine Frage in eine Umfrage ein (we insert a question into a survey).

In In einer Umfrage erklären viele Leute …, why does the verb erklären come before viele Leute? Isn’t German usually Subject–Verb–Object?

German main clauses follow the verb-second rule: the conjugated verb must be in second position, but the first position can be almost any one element (subject, time phrase, place phrase, etc.).

The basic order would be:

Viele Leute erklären in einer Umfrage, …
Subject (viele Leute) – Verb (erklären) – …

Here, the place phrase In einer Umfrage has been moved to the first position to emphasize the survey context:

In einer Umfrage – 1st position
erklären – 2nd position (the finite verb – required)
viele Leute – rest of the sentence

So the word order is due to verb-second syntax, not because viele Leute is no longer the subject. Viele Leute is still the subject and erklären agrees with it (plural).

Why is erklären used here instead of sagen? What is the nuance?

Both are possible, but they have slightly different flavors.

sagen = to say, to tell (neutral, very general)
erklären = to explain, to state, to declare

In the context of a survey, erklären often means to state / to declare in a somewhat formal way. It sounds a bit more official and report-like:

Viele Leute sagen, dass … – many people say that … (everyday speech)
Viele Leute erklären, dass … – many people state that … (more formal, report style)

Survey results, news articles, and reports often use erklären, angeben, or äußern in this way.

Why is there a comma before dass?

In German, dass introduces a subordinate clause (a dependent clause). Subordinate clauses are normally separated from the main clause by a comma.

Main clause: In einer Umfrage erklären viele Leute
Subordinate clause: dass sie nur die Überschrift lesen

German spelling rules require a comma before conjunctions like dass, weil, obwohl, wenn, etc., when they introduce a subordinate clause:

…, dass sie nur die Überschrift lesen.
…, weil sie wenig Zeit haben.
…, obwohl sie es wichtig finden.

In dass sie nur die Überschrift lesen, why is lesen at the end?

In German subordinate clauses, the conjugated verb goes to the end of the clause. Because dass introduces a subordinate clause, lesen must appear last:

Main clause word order (verb second):
Sie lesen nur die Überschrift.
With dass (subordinate clause, verb final):
… dass sie nur die Überschrift lesen.

So the pattern is:

dass
- subject + objects/adverbs + verb (final)
  → dass sie nur die Überschrift lesen

In dass sie nur die Überschrift lesen, who or what does sie refer to? Could it mean she?

On its own, sie is ambiguous in German: it can mean she, they, or you (formal), depending on context and verb form. Here, we have:

Plural subject in the main clause: viele Leute (many people)
Plural verb in the subordinate clause: lesen

So sie here clearly means they, referring back to viele Leute:

Viele Leute erklären, dass sie nur die Überschrift lesen.
→ Many people state that they only read the headline.

In this sentence, sie cannot reasonably mean she, because the reference to a singular female person is missing and the verb lesen is plural.

Why is it nur die Überschrift and not nur der Überschrift or nur den Überschriften?

Überschrift is a feminine noun (die Überschrift, singular). In the sentence, it is the direct object of the verb lesen (to read). The direct object is in the accusative case.

For feminine nouns, nominative and accusative singular look the same:

Nominative singular: die Überschrift (subject)
Accusative singular: die Überschrift (object)

Here we have an object, so it’s accusative, but it still looks like die:

Sie lesen nur die Überschrift.
They only read the headline.

Forms like der Überschrift (dative genitive singular) or den Überschriften (dative plural) don’t fit the role or number in this sentence.

Where does nur usually go, and what does its position in sie nur die Überschrift lesen tell us?

Nur means only and usually stands directly in front of the word or phrase it limits or emphasizes.

In sie nur die Überschrift lesen, nur comes before die Überschrift, so it restricts what they read:

sie nur die Überschrift lesen
→ they read only the headline (not the rest of the article)

If you moved nur, you would change the focus:

Sie lesen nur die Überschrift. – neutral, standard word order.
Sie lesen die Überschrift nur. – still “they only read the headline,” but sounds a bit more marked, slightly emphasizing nur.
Nur sie lesen die Überschrift. – only they (and nobody else) read the headline.
Here nur modifies sie, not die Überschrift.

So the placement of nur determines which element is being limited.

What is the difference between Überschrift and Titel? Could we say nur den Titel instead?

Both relate to something like a headline/title, but they have different common uses:

Überschrift
– Most often: the headline or heading of a text, section, chapter, article, etc.
– Very common for newspaper headlines.
Titel
– The title of a book, film, song, article, etc.
– Also academic titles, job titles, etc. (e.g. Doktortitel).

In a news or article-reading context, Überschrift is the most natural word. Nur den Titel lesen is understandable and not wrong, but nur die Überschrift lesen is the standard phrasing for “only read the headline (of an article).”

Why is it viele Leute and not vielen Leuten?

Viele Leute is the subject of the sentence, so it must be in the nominative case.

Nominative plural: viele Leute – many people (subject)
Dative plural: vielen Leuten – to/for many people (indirect object)

Examples:

Viele Leute erklären, dass … – Many people state that … (subject → nominative)
In einer Umfrage wird vielen Leuten eine Frage gestellt. – In a survey, many people are asked a question.
Here vielen Leuten is an indirect object → dative.

In the original sentence, viele Leute is clearly the subject, so nominative is correct.

Why is the verb erklären plural and not singular (erklärt)?

The verb must agree with the subject in person and number.

The subject is viele Leute:

Leute is plural.
viele makes it even clearer that it is “many people”.

So the verb must be 3rd person plural:

viele Leute erklären – many people state
Singular would be:
- eine Person erklärt – one person states
- die Person erklärt – the person states

Therefore, erklären (plural) is grammatically required here.

Could we also say Viele Leute erklären in einer Umfrage, dass sie nur die Überschrift lesen? Is that different?

Yes, that sentence is also correct. The difference is only in emphasis:

In einer Umfrage erklären viele Leute, …
→ puts the survey (In einer Umfrage) first, emphasizing the context/source.
Viele Leute erklären in einer Umfrage, …
→ starts with Viele Leute, emphasizing who is doing the explaining.

Both follow the verb-second rule and are grammatical; it’s a stylistic choice.

Could we say dass sie nur die Überschrift lesen würden instead of lesen? What would that change?

dass sie nur die Überschrift lesen – present tense
→ reports what they generally do or typically claim to do:
“They state that they only read the headline.”

dass sie nur die Überschrift lesen würden – conditional
→ sounds more hypothetical or tentative:
“They state that they would only read the headline (if …).”

In this context, where people are reporting their actual reading habits, lesen (simple present) is more natural. lesen würden would suggest a hypothetical situation or a softer, more speculative statement, which doesn’t fit as well with survey results.