"Call the dog!"
Translation:Ruft den Hund!
It depends who you're talking to. Just as you'd say du to mean "you" when talking to only one person but ihr when talking to multiple people, when you want to tell someone to do something you need a different form depending on whether you're telling one person or more than one person. This form of 'telling someone to do something' is called the imperative form. Duolingo has an introductory page on it here, and there are others around the internet.
Talking to one person: Ruf den Hund!
Talking to more than one person: Ruft den Hund!
Polite form (any number of people): Rufen Sie den Hund!
I believe Duo should be accepting both Ruf den Hund! and Rufe den Hund! It rejects the latter. Is rufe no longer used? I reported it. (But that won't help me pass the "skip level" test, in which I'm now down to one heart.)
These "skip level" tests in the crown system are turning me into "an annoying, stereotypical, grade-sucking student." Not that I'm not still working hard to LEARN German.
I just got a notice that Rufe! is now accepted. Thanks! That was super fast! Also thanks for the advice. I will definitely use Ruf!
Note: 201 German Verbs lists rufe! ruft! rufen Sie! No mention of ruf! However, my copy of 201 is copyright 1964. Yikes! But the price was right. I suspect the latest 501 lists ruf! and quite possibly no rufe!
P.S. I passed the test with 0 hearts. A bit humbling.
For the same reason that we would say, “Call him!” and not “Call he!” — the dog is the direct object of the verb rufen and so has to be put into the accusative case.
Since Hund is masculine, the accusative case looks different from the nominative case: nom der Hund becomes acc den Hund.
(Feminine, neuter, and plural words always look the same in the nominative and accusative cases.)
How are we suppose to know if they are talking to one person or several?
You aren't. The English sentence is ambiguous and so both German translations (singular or plural) are accepted.
It marks Ruf as incorrect
Well of course. The single word Ruf does not mean "Call the dog!".
Ruf den Hund! would be accepted.
(Do you have a screenshot showing that sentence being rejected?)
I was only typing the word which was said to be incorrect.
Lots of people make mistakes in word order or articles or some other place than the one which they think they got dinged for. Please always quote your entire answer.
I've learned never to assume anything about the rest of the sentence, simply because I've seen so many different kinds of mistakes.
Of course I typed Ruf den Hund.
Then I will assume that it was accepted, unless you have a screenshot showing otherwise.
Please read through the comments before asking a question, because your question has been raised and cleared on multiple occasions in this discussion already:
For the translation of "Call her" I wrote "Ruf sie an" and it was marked correct. For this sentence I tried the same "Ruf den Hund an" and it was marked wrong. I'm guessing anrufen is more suited for calling a person as in a telephone call. Can anyone confirm?
Yes, anrufen is basically to call someone by phone. rufen is usually only to call someone with your voice, i.e. they are in earshot and close enough to hear you.