Was heißt »fruchtlos« auf Englisch?

Das Adjektiv fruchtlos lässt sich wie folgt von Deutsch auf Englisch übersetzen:

Deutsch/Englische Beispielübersetzungen

Wir waren in eine fruchtlose Debatte verwickelt.: We were involved in a petty argument.
Nach drei fruchtlosen Versuchen probierte er es noch ein letztes Mal.: After three fruitless attempts, he tried one last time.
Es wäre fruchtlos, die Heilige Schrift nach nur einer einzigen Stelle durchsuchen zu wollen, an der Jesus Frauen nicht dem Manne entweder gleich- oder höhergestellt behandelt.: It would be a fruitless search to look through the Scriptures and find one single instance where Jesus did not treat women either equal or superior to men.

There were once a man and a woman who had long in vain wished for a child.
I tried in vain to convince her.
All help is in vain.
Tom tried in vain to hide his pain.
We tried in vain to cheer Tom up.
His sacrifice will not be in vain.
"Think of me when you go back to Australia," Mary told Tom, as she tried in vain to hold back her tears. "When shall I ever see you again?"
At least, he did not die in vain.
Your son did not die in vain.
Your son did not die in vain. He died a hero.
Your son did not die in vain. He died fighting for his country.
Tom did not die in vain. He died a hero.
He didn't die in vain.
It's a sin to use the Lord's name in vain.
In vain have I tried to convince him.
Tom tried in vain to convince Mary to go to art school.
He's lazy and vain.
It's good to see that our efforts were not in vain.
I waited all afternoon in vain.
But there was no sign of him, and it was in vain that I shouted.