That is not correct for two reasons: first, "tanár" is a male teacher (the female one is a "tanárnő"), second, in that case you would not use the definite article: A tanárnő gyereket vár.
True, but sometimes you can say tanár for both genders. And about the article, that's also true. But the original sentence could also possible be interpreted as the teacher being pregnant. Your points are valid though.
Both have the same meaning. Maybe "gyermek" is more used for the "little child"(gyermek/kisgyerek). But the older kids also do not be offend from that word.
Are you serious? The teacher is waiting for a young goat? Maybe allowable in English but not the preferred correct translation.
Mi a különbség a wait és az await között? Én azt írtam, hogy The teacher waits a child. Hibát jelez a duo. Javaslata: The teacher awaits a child. Nem értem a különbséget. Tud valaki segíteni?
/wait=stay in one place/ vagyis várni valamire /await=looking forward/ tehát valami várhatóan bekövetkezik. ezt egy angol oldalon találtam remélem érthető így.
I'm still trying to get my head around this - is 'egy' definite article or indefinite? Or does it depend on whether it's nominative or accusative?
"Egy" is an indefinite article, while "a" and "az" are definite articles. Articles do not have nominative and accusative forms. BEWARE: "egy" is also a numeral ("one") and "az" is also a demonstrative pronoun ("that"), and as such, they can have accusative forms: "egyet", "azt".