Forming questions with German.
Can someone please explain how to form questions in German? Both Yes and No and Question word questions.
These are covered in the Questions 1 and Questions 2 skills.
I copy-paste the Tips and Notes for you:
Yes/No Questions Questions can be asked by switching the subject and verb. For instance, "Du verstehst das." (You understand this) becomes "Verstehst du das?" (Do you understand this?). These kinds of questions will generally just elicit yes/no answers. In English, the main verb "to be" follows the same principle. "I am hungry." becomes "Am I hungry?". In German, all verbs follow this principle. There's no do-support.
Asking a Question in German With a W-Word Seven W-questions - "Wer" (Who), "Was" (What), "Welche/Welcher/Welches" (Which), "Wo" (Where), "Wann" (When), "Warum" (Why), and "Wie" (How) - can be asked in German to elicit more than yes/no answers. Three of the seven adverbs are declineable (i.e. change with the case), whereas four are not.
wer (who) "Wer" is declinable and needs to adjust to the four cases. The adjustment depends on what the question is targeting.
If you ask for the subject of a sentence (i.e. the nominative object), "wer" (who) remains as is: "Wer sitzt da?" (Who is sitting there?). If you ask for the direct (accusative) object in a sentence, "wer" changes to "wen" (who/whom). As a mnemonic, notice how "wen" sounds similar to "den" in "den Apfel." "Wen siehst du?" (Whom do you see?) - "Ich sehe den Sohn" (I see the son). If you ask for the indirect object, "wer" changes to "wem" (who/to whom) and adjusts to the dative case. You could ask "Wem hast du den Apfel gegeben?" (To whom did you give the apple?) and the answer could be "Dem Mann" (the man). Notice again how the declined form of "wer" ("wem") sounds like the definite article of all masculine and neuter nouns in the dative case (like "dem Mann" or "dem Kind"). Lastly, asking about ownership (genitive case), changes "wer" to "wessen" (whose). "Wessen Schuhe sind das?" (Whose shoes are these?) - "Das sind die Schuhe des Jungen" (These are the boy’s shoes). And notice once again how "wessen" (of the) and "des" (of the) include a lot of s-sounds. was (what) Similar to the changes made to "wer," "was" will decline depending on the four cases.
For both the nominative and accusative cases, "was" remains the same. It is common to ask "Wer oder was?" (who or what?), if you want to know more about the nominative object and do not know if it is a person (who) or a thing (what). You ask "Wen oder was?" (who/whom or what?), if you want to know more about the accusative object. "Was" changes to "wessen" for questions about the genitive object as in "Wessen ist sie schuldig?" (What is she guilty of?). For the dative, "was" changes to a compound of "wo(r)" + preposition. For instance, if the verb takes the German preposition "an" (on/about) as in "an etwas denken," you would ask "Woran denkt er?" (About what is he thinking?). Likewise, "hingehen" is a verb composed of "gehen" + "hin" (go + to) and you would ask "Wohin geht sie?" (To where is she going?). welche/welcher/welches (which) "Welch-" words are used to ask about for a specific item out of a group of items, such as "which car is yours?".
This declines not only for case, but also for gender, in a way very similar to adjectives.
wo (where) In German, you can inquire about locations in several ways. "Wo" (where) is the general question word, but if you are asking for a direction in which someone or something is moving, you may use "wohin" (where to). Look at: "Wo ist mein Schuh?" (Where is my shoe?) and "Wohin kommt dieser Wein?" (Where does this wine go?). Furthermore, "Wohin" is separable into "Wo" + "hin." For example, "Wo ist mein Schuh hin?" (Where did my shoe go?).
Note that the sound of "Wer" is similar to "Where" and that of "Wo" to "Who," but they must not be confused. In other words: the two German questions words "Wer" (Who) and "Wo" (Where) are false cognates to English. They mean the opposite of what an English speaker would think.
wann (when) "Wann" (when) does not change depending on the case. "Wann" can be used with conjunctions such as "seit" (since) or "bis" (till): "Seit wann haben Sie für Herrn Müller gearbeitet?" (Since when have you been working for Mr. Müller?) and "Bis wann geht der Film?" (Till when does the movie last?).
warum (why) "Warum" (why) is also not declinable. "Wieso", "Weshalb", and "Weswegen" can be used instead of "Warum." There's no difference in meaning. For example, take "Warum ist das Auto so alt?" = "Wieso ist das Auto so alt?" = "Weshalb ist das Auto so alt?" = "Weswegen ist das Auto so alt?" (Why is the car so old?).
wie viel vs wie viele "wie viel" is used with uncountable or countable nouns (how much/how many), and "wie viele" is only used with countable nouns (how many). Some people think that "wie viel" can only be used with uncountable nouns, but that is not true.
Wie viel Milch trinkst du? = How much milk do you drink?
Wie viel(e) Tiere siehst du? = How many animals do you see?
Please, read the grammar "Tips and notes" in Duolingo's web version on the bottom of the Lessons page of the skills "Question 1" and "Questions 2"
Additional grammar explanation:
- Indirect questions