Wrong on Nominative/Accusative?
I was asked to translate:
He is a teacher.
I gave it an answer "Er ist einen Lehrer" because I thought "a teacher" was the object and therefore accusative and therefore einen instead of ein.
The answer says that "a teacher" is nominative. Am I missing something?
Yes, it's a predicative expression: http://en.wikipedia.org/wiki/Predicative_(adjectival_or_nominal)
I don't remember the rule, but when the verb "zu zein"(ich bin, du bist ...) is used to describe the subject it's nominative. There are a couple of other verbs as well.
As a general rule you can use nominative if it points to the subject ie: He is a teacher. and accusative when it's points to the verb