"a curse that" is a correct and usable part of a sentence in written English.
For example, you could use it in a sentence such as: "He was under a curse that had haunted him since childhood."
"It was like a curse that followed him," Skrzynski said.
Because mindlessness is a curse that runs through society.
Sids was once a curse that struck randomly across classes.
There is a curse that strikes terror into the most intrepid traveller's heart.
Dull filmmaking and spiritless dialogue can together feel like a curse that hangs over actors, stifling their every other scene.
(Pocket, $5.50). The origin of a curse that has haunted a family of orphans in five previous novels.
There is a curse that befalls those film directors who try to adapt Don Quixote for the screen.
Lilliet believes that she operates under a curse, that before long her voice, too, will break down.
Many people felt Banda Aceh was doomed by a curse that had yet to run its course.
A novel-length narrative about a boy under a curse that prevents him from aging beyond 17.
