"Der Mann isst mit dem Lehrer."
the submit error button is limited in options, so i elaborate here: for my answer I typed 'der Mann ist mit dem Lehrer', which is wrong, but it marked it as correct and did not mention my typo either.
I did the same, and was marked as correct when I should not have been. (Or at least should have had a warning)
"dem" is audible for me as a native speaker and listener. Also, the "mit" preposition indicates that a singular, dative object is about to follow. There are multiple correct answers, for instance "The man [eats/is eating] with [the/that] teacher."
It says there are 2 correct answers but there should be only one. "The man eats with that teacher" is translated into german like " Der Mann isst mit diesem Lehrer"
what is the difference in pronunciation between isst and ist? I keep on making the same mistakes when listening and not reading
There is no difference. "Man ist, was man ist" and "Man ist, was man isst" are both meaningful and sound the same but have different meanings
Because: mit+Dative; "der Lehrer" (masculine) becomes "dem Lehrer" in Dative
Dem is used for "The" when using the Dative case for Masculine or Neuter nouns. Den is "The" for masculine Accusative nouns or plural dative nouns. After "mit" the noun that follows always takes the dative case.
If this isn't clear then you need do a web search on german definite articles