Why Ich sehe ihr means I see her?
I thought "ihr' meant you. However, duolingo indicates that ICH SEHE IHR means "I see her" instead of "I see you" Why?
I don't understand it either. Ihr can mean she, but then it's Dative case. Shloudn't we use Accusative here? Isn't her direct object... or? I'm confused here but it can't mean "I see you" as you proposed because if Ihr means you it's nominative and you can't use nominative of ihr in your example. I think "I see you" would be "Ich sehe euch". But i'm not sure.
btw check this: http://en.wikipedia.org/wiki/German_pronouns#Personal_pronouns
The only question is what case shloud you use? If it's really Dative as indicated by Doulingo then "Ich sehe ihr" really means "I see her" bacause ihr is Dative case of sie.
That strikes me as being wrong. "Sehen" is a pretty standard action verb so the direct object should be accusative. The sentence "Ich sehe Ihr/ihr" is grammatically incorrect.
In general though one trick to notice the difference between pronouns for "she"/"them" and "You (Formal)" is to check for a capital letter. "Ich sehe Sie" is "I see You (formal)" but "Ich sehe sie" is I see her/them. Obviously if this question was audio then that doesn't really help!
*Edited for mistakes pointed out by Nachdenklich.
'Ihr' does mean you. However, it is also the dativ form of 'sie' (she), and possesive of 'sie' (she) and 'Sie' (you formal).
However, in this case, the sentence is false because with 'sehen', you have to use to accusativ. So the possibilites are:
Ich sehe sie. (I see her) or Ich sehe dich (I see you)