I completely disagree (for what it's worth, and respectfully). I need to know what the native speakers are really saying. It's their culture, their language, their way of thinking. This tells me that they think of "plate" the same way they think of "bowl," or that plate is a bowl, just flatter, and this may lend itself to something on the origin of plates and bowls, etc (just to get silly here). To understand the language like a native, I can't keep thinking like a-something-else. What they are really saying is what I want to know. "Translation" is what doesn't work, not for me. So I spend time learning what the words really mean, then change that into what Duolingo seems to expect. That is what works best... for me, at least. Otherwise this language becomes a "patch" on top of my native language, and I really haven't learned it at all.
It's on the plate, at office, in the car and back home.
. . . but why is it not:
in the plate, on the office, at the car and out home . . . ?
In Italy it's nel piatto, in ufficio, in macchina, a casa.
So even if the literal translation of this sentens is that the forks are "in the plate" that's not a good translation, - as that is not the way this sentens would be phrased in English.
In Italian things can still be "sul piatto", - in the same way as in English things can be "on top of the plate". Perhaps when searching for the lost keys and somebody suddenly points saying: "They are there, - on top of the plate!"
Just yes or no? That's a little vague. On just yes or no, I have to say "Yes!!" (I clicked your up arrow.) But there are about 88 things I'd like to see fixed, improved, changed (hazards of being a long-time, high-end computer programmer... no software ever looks really good to you again :) )
"...nello piatto" is wrong because "piatto" doesn't begin with a vowel, a zed, or an impure ess (ess followed by another consonant). "nel" is a contraction of "in il" and "nello" is a contraction of "in lo", the only distinction being the word they would precede, as we would say "a plate" or "an apple" in English.