It is generally a bit impolite to say "du" to an unknow person. But I can say to a child: "Oh, du sprichst Deutsch!" and that would sound kindly. Otherwise it would sound shirt-sleeved if I say to an adult: "Du bist Türke. Du sprichst Deutsch." I think this has a foreign sound.
Is necessary to use always the pronouns? I mean for example, in spanish you can say Tú hablas (du spricht) or you can say Hablas without the pronoun because the conjugation gives the idea of the person who is speaking, so in german Can I say spricht without the pronoun "Du" like In Spanish?
There are two forms of "you" in German (like in French and other languages too). Sie (capitalized) and the possesive pronoun Ihr/Ihre (your) is more polite, du and dein (your) in the singular and ihr (you) and the possesive pronoun euer in the plural is more familiar. I say "du" (and ihr) to children, to my relatives and friends. I say "Sie" to unknown persons and to the most of my neighbours and colleagues. Say "Sie" if you don't know which of both and perhaps somebody says: "Sag du zu mir. Ich bin der Hans (or die Marie for example)."
No. When the combinations st or sp come at the beginning of a syllable, they are pronounced as scht, schp -- for example, spielen and Stein are pronounced as schpielen and schtein.
(But not at the end of a syllable; for example, du gehst is not pronounced du gehscht, and Wespe "wasp" is Wesp-e and so is pronounced Wesspe and not Weschpe.)
I have a question I'm going to ask randomly on this post. It seems to me that Duolingo really emphasizes the informal "du" and "ihr" over the formal "Sie". I'm studying German for an upcoming trip to Austria. Surely I should be using the formal forms with strangers I meet? I would think that is the case with most folks studying a foreign language. I'm not going to be communicating with my friends and family in German, just with strangers.
Shouldn't it be "Do you understand German?".
Yes-no questions start with the verb, as in Verstehst du Deutsch? "Do you understand German?"
But this sentence has the verb in the second position, as is normal for a statement: Du verstehst Deutsch. "You understand German."
You understand German, or you are understanding German are the same.
No, they are not.
The first is natural American English, the second is not.
"English" on Duolingo is US English by default, and regionalisms such as "I am understanding the problem" that you might hear in (say) India are not generally accepted on this course.
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