un iaurt - a yogurt (n sg indef)
iaurtul - the yogurt (n sg def)
iaurturi - yogurts (n pl indef)
iaurturile - the yogurts (n pl def)
Produs lactat cu un gust acid plăcut și cu aromă specifică, preparat din lapte de vacă, de oaie, de bivoliță sau de capră
Dairy product with a pleasant acidic taste and a specific flavor, prepared from cow, sheep, buffalo or goat milk
No. 'strugure' grape which is masc. also ends its plural in - uri. I will try to look up some rule.
Ok. I changed my mind; I think you are right. 'struguri' is rather exceptional because it has 'ur' in the word stem. Another one like this is iepure -iepuri - (m) rabbit
But I am a learner as you, I might be wrong....