Hier ein Beispielsatz aus dem Free Dictionary:

I made all the arrangements, bought the ticket, and even took him to the airport, but he just wouldn't get on the plane. Well, you can lead a horse to water, but you cannot make him drink.

Das ist aber ein Zufall. Ich hab genau dieses Idiom gestern in meinen alten Englisch-Schulsachen gelesen.

Hier ist noch eine Definition aus dem OALD:

you can lead / take a horse to water, but you can't make it drink
= (saying) you can give sb the opportunity to do sth, but you cannot force them to do it if they do not want to

Hoffe, ich konnte dir helfen.