Translation:What day of the week do you go running?
@Ekrem_G - Actually, you are totally correct. You are asking for clarification: "Which days did you say you were running?" versus "What day is it today?"
"Which" is correct here; "What" is a second best. You'll use "which" in a sentence that can read like this: "Which days of the week are the busiest for you?"; or "Which day did you say you were free again?"; etc. "Which" will point to the subject of a conversation being discussed, something that needs clarification.
So, "Which day of the week is it?" would automatically imply there was a conversation about that day, but you cannot remember the details and you are asking the person to repeat themselves.
Have an ingot! :)
Question words are placed where the answer would appear in a statement.
星期六你跑步 = You run on Saturday.
星期几你跑步 = On which day do you run?
你是美国人 = You are American.
你是哪国人 = Which country are you from?
你跑了三个星期的步 = You ran for three weeks.
你跑了几个星期的步= How many weeks did you run?
I believe you are right because when you do a verb for a certain amount of time (duration), then the time comes after the verb. I'm making my first attempt through the tree and remembering all the grammar rules has been hard. I am still trying to learn the correct way to use separable verbs and objects. Thank you for pointing this out. I will change it.
The supplied English answer is grammatically incorrect outside the USA. As other people have posted, it should be "which" not "what" because you are selecting from known options. In addition, the sentence should start with "On".
On the plus side, this is making me realise how subtle good English grammar is and how difficult it must be to learn as a second language.
1) In the word bank, 几 (jī) and 去 (qù) stand together, while they don't belong together at all;几 (jī) refers to 星期 (xīng qī)! It's fine if the characters 星期 几 (xīng qī jī) are placed together in the beginning to teach the meaning "which day (s) of the week", but you can let go this contraction later in the course; the student must then decide for himself how that should be translated. The same applies for eg 手机 (shǒu jī) for mobile phone, and other words with more than one character. Now it makes the word choice more limited; Duolingo gives the translation already away: the students don't have to think for themselves. Plus, by offer it this way: how will they ever get to the point where they can write independently in Chinese (for the time being just digital)? = = =
2) About the pronunciation by the female voice during these exercises:
In the quick version of "Tap what you hear" I don't hear "pǎo" but "Kǎo".
In "What sound does this make?" it's even worse: at 运 (yùn) I hear: qì (or) pì (or) bì (or) tì ....!
I have had lessons in a class with different textbooks and methods, but I have NEVER witnessed any characters being linked to each other that absolutely do NOT belong together! If teachers do, it only shows that they have absolutely no insight into how you can best teach others a foreign language, whatever that language is!
Nor is it the other way around: a new character - that later in the lessons returns in a combination that TOGETHER have a certain meaning - "learning" by showing and hearing that one character, whereby the student, based on 3 given sounds, has to make a choice, without mentioning the meaning of that character (because in many cases it has a separate meaning that is irrelevant in the combination with the other character that the student only learns later in the lesson): it's a complete waste of time! Incidentally, the learning methods and books that we used at the time were far from ideal, but (remarkably enough): their quality deteriorated considerably if native Mandarin speakers apparently had (too) much influence on the teaching methods… ..! There will certainly be native Mandarin speakers who can teach well, but it is clear to me that they have NOT contributed to the Duolingo lessons, nor to the HSK books (which even constitute the internationally recognized standard method .....) !