Adjective's meaning being determined by other parts of sentece?

Question

Mit seiner Fülle von Informationen und Attraktionen ist ein Freilichtmuseum ein für alle Altersklassen geeigneter Tagesausflug mit pädagogischem Hintergedanken für die ganze Familie, der sich zum Beispiel in den Schulferien anbietet.

Could someone explain to me the grammar of the highlighted part?

I believe that "ein für alle" is an adverb modifying the verb, but the problem is, it seems to be forming a meaning with geeigneter (adjective) together. As in, it tells us what sense "the suitableness" occurs and Altersklassen is the object of who it's suitable for.

Related: 1 , 2

Answer 1

Let me translate the sentence for you:

Mit seiner Fülle von Informationen und Attraktionen ist ein Freilichtmuseum ein für alle Altersklassen geeigneter Tagesausflug mit pädagogischem Hintergedanken für die ganze Familie, der sich zum Beispiel in den Schulferien anbietet.

With its wealth of information and attractions, an open-air museum is a day trip suitable for all ages, with an educational background for the whole family, which is ideal during school vacations, for example.

^{(Altersklasse is in fact "age class", and so "für alle Altersklassen" is literally "for all age classes", but I think "for all ages" sounds better in English.)}

First of all, let's eliminate all parts of speech, that we don't need. To do so, we first need to find the verb, which is »ist«. This is a copula verb, so it needs two supplements, and both of them in nominative case, and one of them must be the subject. Then the other is a »Gleichsetzungsnominativ«:

Ein Freilichtmuseum ist ein für alle Altersklassen geeigneter Tagesausflug.
_{An open-air museum is a day trip suitable for all ages.}

• Ein Freilichtmuseum
  _{An open-air museum}
  Subject
• ist
  _is
  Verb (copula)
• ein für alle Altersklassen geeigneter Tagesausflug
  _{a day trip suitable for all ages}
  Gleichsetzungsnominativ (equative nominative)

Now, let's dive deeper into the last nominal group. It's core is the noun »Tagesausflug« (day trip) which is a masculine noun. It has an indefinite article as a determiner (»ein«), and these two words already would give a complete nominal group, that could stand in a sentence:

Ein Freilichtmuseum ist ein Tagesausflug.
_{An open-air museum is a day trip.}

But the core noun has an attribute, that describes it further: »geeigneter«. This is a declined form of the adjective »geeignet« (suitable), and adding this adjective as an attribute left of the noun, we have another correct sentence, but now with a little bit more information about the day trip:

Ein Freilichtmuseum ist ein geeigneter Tagesausflug.
_{An open-air museum is a suitable day trip.}

But now, this adjective itself also has an attribute, which is a nominal group, and this attribute tells us for whom this day trip is suitable: It's suitable »for all ages«. In weak English:

An open-air museum is a for all ages suitable day trip.

But when in English an adjective, that is an attribute by itself has it's own attribute, then it no longer can stand left of the noun. It must move to the right side of the noun:

An open-air museum is a day trip for all ages suitable.

And also the adjectives attribute must move from the left side to the right side of the adjective:

An open-air museum is a day trip suitable for all ages.

But these shifts are not necessary in German:

Ein Freilichtmuseum ist ein für alle Altersklassen geeigneter Tagesausflug.

the adjective, being the nouns attribute, stays left of the noun, and the prepositional group »für alle Altersklassen«, being the adjective's attribute, also stays left of the adjective.

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Let me add, that also this is a correct sentence:

Ein Freilichtmuseum ist für alle Altersklassen ein geeigneter Tagesausflug.
An open-air museum is for all ages a suitable day trip.

Here the prepositional group »für alle Altersklassen« is no longer an attribute of the adjective »geeigneter«, but it's an adverbial clause and belongs to the verb »ist«. (This is also true for the English translation that has the same structure.)

Answer 2

You can use a bracket notation to make clear what is going on - if you find it helpful (the italicized part is the adjective group):

• ein [ [für alle Altersklassen] geeigneter] Tagesausflug

Also, it may help to note that a less convoluted way of saying the same thing is a relative clause. It contains the same chunk of words in the same order:

• ein Tagesausflug, [ der [für alle Altersklassen] geeignet ist]

Answer 3

When reducing the sentence to

Ein Freilichtmuseum ist ein Tagesausflug.

it should be obvious, that this is nonsense. Because

Ein Spatz ist ein Vogel.

and

Ein VW Golf ist ein Auto.

but an open air museum cannot be a day trip. An open air museum could be worth a day trip, like in:

Dieses Freilichtmuseum ist einen Tagesausflug wert.

However, the formal dissection above is correct, everybody will understand the intention of the writer, but it's just bad German.