┏━━━━━━━MAIN CLAUSE━━━━━━━┓ ┏━━━━━━━━━━━━━━RELATIVE CLAUSE (subordinate clause)━━━━━━━━━━━┓
Es ist {kein Faden}ᴺᴼᴹ , der vorne {einen Anfang}ᴬᴷᴷ und hinten {ein Ende}ᴬᴷᴷ hat.
Literally: "It is no thread that has in the front a beginning and in the rear an ending."
This is a compound sentence with a relative clause separated with a comma (!) and introduced with der
used as a relative pronoun.
In the main clause, kein
is the negating indefinite pronoun used attributively of a noun (kein Faden = no thread) that governs the inflection of the indefinite pronoun: singular masculine. The noun phrase kein Faden
is in the nominative case because it is the object of the verb ist
(sein).
The relative clause describes the object noun Faden
, therefore the relative pronoun der
, referring back to 'Faden', is inflected in agreement with it: masculine singular, nominative.
The noun phrases einen Anfang
and ein Ende
are in the accusative case because they are objects of the verb hat
(haben).