Student or Learner
In this sentence: "They stuck by their decision."
What does stuck by mean? Does it mean "they did what they promissed/planned" or "they did not want to change their decision"?
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.
The first. Probably the second too, - but they certainly didn't change their minds. (And it's promised - your mistake makes sense though. It's not /'prɒmaɪzd/, so a double-s might be expected; it's just wrong. )