"He is not looking at the car."
Translation:On se na to auto nedívá.
My wrong answer was corrected to "On na to auto nekouká." What?!
It isn't at all helpful to know that there is some other verb in the language that comes close to fitting my failed attempt at the proper word order; I need to learn the correct way to use THIS verb. It's very confusing (and frustrating) when the "right answer" contains vocabulary that hasn't even been introduced.
It can indeed be confusing and frustrating when it seems like we're supposed to know something that hasn't been presented yet! The DL system generates "correction" answers based on what we enter. If we enter something that's not close enough to what it expects to see, it offers an option that -- in its wisdom -- "improves" on what we give it. I don't know what your complete answer was, but maybe it didn't include "se." So DL provided an alternative valid translation that included a verb that does not use "se." (Just a guess, though...)
That's a useful thing to know, as well as knowing for this sentence here, Duo has 103 possible correct answers, according to kacenka9's post above.
Apparently, mine isn't one of them. "Nedívá se to na auto."
So what's wrong? "Se" is in the second place. Used the third person singular form of the verb with the proper negation. "To" is the proper demonstrative article for the singular accusative neuter noun 'auto.' Maybe duo doesn't like that I didn't use "on" as the subject?, but that's not required in Czech, right? My words are spelled and accented correctly. . . hmmm
Wait! There is is! It should be 'na to' instead of 'to na'!!!!
Wow. That was exhausting. Potřebuju kávu.
Some verbs include "se" as part of the verb itself, and we just need to learn which ones they are. Some that you may have run across so far are dívat se, starat se, bát se, and ptát se. They are generally covered in the Tips & Notes sections for the Skills in which they appear (T&N are web only currently; click a skill, then click the light bulb icon). You can also find some information about reflexive verbs at this link (it's pretty far down the page): https://mluvtecesky.net/en/grammar/verbs.