This is the 14970th most frequent German word.
schliessen
"Schließen" means "to close" or "to shut" in English.
The word 'schließt' here is used in its literal sense to mean 'closes', indicating the action of securely shutting the door.
Er schließt die Tür leise.
He closes the door quietly.
The word 'geschlossen' (past participle of 'schließen') is used to indicate the completion of an event or activity.
Die Veranstaltung wurde mit einer Rede des Direktors geschlossen.
The event was concluded with a speech by the director.
The word 'abschließen' is a compound verb formed with 'schließen', meaning 'to complete or conclude', in this context referring to finalizing an agreement.