"I am your grandfather."
Translation:Ich bin dein Großvater.
You mean "Ich bin Ihr Großvater." In theory this could be said. Here, "Ihr" is the formal address meaning "you".
However, if you are someone's grandfather, in most cases you'd be pretty close to them, so to use the informal address "Ihr" would be rather unnatural.
However, it could still be said in a situation where a grandfather doesn't know his grandchild, may it be due to divorce or for whatever reason. The grandfather might meet the grandchild for the first time when the grandchild is an adult. In that case, it is certainly feasible to say "Ich bin Ihr Großvater." It's just not very common.
Exactly. You always use the nominative after the following six verbs:
1 bleiben to stay, remain
2 gelten als to be regarded as
3 heißen to be called or named
4 scheinen to seem 5 sein to be
6 werden to become (see: http://www.byki.com/lists/german/german-verbs-that-take-a-predicate-nominative.html) The nominative 2nd person pronoun is "dein-" "Großvater" is singular masculine, so the appropriate (weak) ending is none...and you end up with "dein."
Not quite. "Dein Großvater" is in nominative, however, it is not the subject of the sentence, in fact, it's not even the object.
Oh, and, "I" is the subject of the sentence, of course.
You can type two
s instead. It will be accepted.
If you're on an Android device, hold down the
s key on the keyboard. A context-menu with special characters should show up, one of which should be
On a Windows PC, open Notepad and hold down the Alt-key, then type 225 on the number keypad. Release the Alt-key and the
ß should appear. Copy and paste into your browser.
To open Notepad, click the Start button, choose Run, type
Notepad and hit Enter.
Dein Großvater is not an accusative object in this sentence. It's in nominative. I'm not sure it's even considered an object, at the least it's a special scenario with the use of a conjugated form of
sein - “to be“.
Using a different verb which places the (object) noun in accusative shows the proper declension of the pronoun you mentioned:
Ich sehe deinen Großvater. - I see your grandfather.
You don't call a sentence nominative or accusative. Individual nouns are nominative or accusative (or dative or genitive). Each noun gets a case based on its function in the sentence. "Ich" is the subject, so it's nominative, and since we're using a linking verb ("bin"), "dein Großvater" also goes in nominative.
In the sentence "Ich sehe den Großvater des Junges," "Ich" is again nominative, and since "den Großvater" is the direct object of "sehe," it's accusative. "Des Junges" is possessive, so it's in the genitive case.
You can read more here.