Possessive Adjectives in Accusative Form -unsren/unseren
Regarding the accusative case of unser, I read it here (http://german.speak7.com/german_pronouns.htm) that you add an 'e' for the feminine noun, ie., unsren for the muscular noun and unseren for the feminine noun. However, in the Acc. Pron lessons, I encountered a sentence "Er hat unseren Hund." Since 'Hund' is a masculine noun, should it be unsren instead of unseren? Or the rule is an old rule and is not used in the modern German? Could someone please clarify? Thanks!
As a whole, both the "unsren"-type forms and the "unseren"-type forms are ok, but in general, you will only see it written with that -e- in the middle (unseren, unserer, unsere, etc.), especially in more formal writing, whereas you will often hear it pronounced as "unsre" or "unsren".
and unseren for the feminine noun
Just to clarify, the accusative form for masculine is "unseren" and for feminine is "unsere" (I know that's what's written on the website you linked to, you just might have had a typo in your post)
Seems there is a mistake on that webpage. This sentence you are refering to is wrong.: "Note that we add an “e” when we deal with the feminine, either in the singular or the plural; I put it between parentheses above."
That middle "e" mentioned on that page, is not for declaration of feminin or masculin. It is just a stylistic thing. Using the word with "e" is more formal, without more collegial.
It would be:
maskulin: "Er hat unseren Hund." = "Er hat unsren Hund."
feminin: "Er hat unsere Hündin." = "Er hat unsre Hündin."