I would like to know the answer too. My guess is that 'lei ha piatti' means that she has plates in general. But if we say that she has THE plates perhaps we have to realize which plates we are speaking about out of context e.g. I just asked you where are the dirty plates?
In Italian class last year, I was taught that I should always use the articles. I was being taught by native speakers. I suppose they could have been teaching that just because we were beginners, but I figure that it'd be best to just follow what they said. :)
Lei is her, more commonly used to interpret than a formal you when you take the article out it means she has plates. This is grammatically correct too.
Is there any difference in pronunciation between "ai" and "ha i"? Certainly, there is no confusion but it would help if it was possible to distinguish them by sound, not only by context.
Use gli for masculine plurals in which you would use l' or lo in the singular.
If they start with a vowel, or s+ a conssonant, or z, there may be a couple others but those are the ones I'm sure about.
I accidentally omitted "the," and it was still counted as correct. Is this a mistake? Should I report it?