Is the "de" obligatory or not ? When do we have to put it or not ?
I hope I'm not missing anything: if there are more than or equal to 20, you need the de.
A agree with you, this is what I learnt at school. But there were the sentence with "de" and without "de", both correct.
Are there exceptions ?
Hmmm, I think skipping the de is accepted. The amounts on banknotes are written without it (una mie lei) and the prices too (123 lei).
Multumesc ! :)
Why curele and not cureaua???
500 requires the plural, curele; cureaua = the belt (singular).
Btw, I got the question at the first question mark ☺.
Is centură a specific kind of curea ?