relentless

This was achieved only by a relentless program of technical advances.

The successful World Cup bids of both Russia and Qatar have come under relentless scrutiny that has ultimately changed little.

Make way not for ducklings but for relentless darkness: so the operative mantra goes.

Stasio and his team found U.S. forces under relentless assault from insurgents, roadside bombers, and mortar attacks.

Now it is a race against time to see which moves faster—those suffering from the relentless problems or those who can stop them.

But "the cards never forgive," and as a rule Dame Fortune is relentless to the reckless player.

No, there was nothing to worry about as long as that relentless hunter of criminals known as the Black Hood kept off their tail.

It wouldnt be so bad, she said, Gales arm about her shoulders, if Relentless Rudolph would stop laughing.

But the relentless old man went on: 'My lords, to tear from the evil fruit its whole covering, I have but two words to say.

You were relentless, you pursued it to perfection, you laid our motives bare and you beat them raw, each and every one.