Can お be used before any noun or are there rules saying it can only be used before specific nouns? I've seen it being used mainly while talking about food or money, for example, before words like ちゃ, さけ and かね。Is the お prefix used only in formal settings? Can it be omitted in informal settings?
There are two common honorific prefixes in Japanese: お and ご. Both can be written with the kanji 御. Usually (though not always), words of Japanese origin will take お and words of Chinese origin will take ご, though there are exceptions, especially for words of Chinese origin taking お instead (like お茶/おちゃ). Usually, this is optional, but some words almost always take the honorific. A lot of foods/drinks always have the honorific. So, you just have to memorize which words always take it and which ones they take. In general, you can add it to words to make them more polite or to specify that they are someone else's. I would suggest you look at more native examples and try to figure out what honorifics are used in what situations and try to apply that in your own speech.
on wikipedia it is said that being polite in such a way is much more common for females, so maybe the "お" makes you appear too female if you are a man?
(german wikipedia article: de.wikipedia.org/wiki/Geschlechtsunterschiede_im_gesprochenen_Japanisch
there is also an english article but it is not as extensive: en.wikipedia.org/wiki/Gender_differences_in_spoken_Japanese
i know wikipedia is not the most reliable source, but at least there are some differences in the language of women and men)
There are definitely gender differences in Japanese relating to the use of お, but for certain words, for example お水, おちゃ, おふろ, the addition of お is not seen as feminine. I'm afraid I can't give you a reason why though, and I suspect native speakers will have a hard time explaining it too.
It's not that simple. Please have a more thorough read of the other comments in this thread.
It would be wise to keep in mind that, because Japanese and English are such different languages, with different cultural and linguistic history, it's very rare to find phrases/sentences that perfectly line up with each other in terms of meaning, politeness and usage. Also because English is so widely used, what's polite for me might not be quite as polite for you, or it might be more polite/too polite, so no one will be able to definitively answer your question.
Yes, all those variations are correct and meaning exactly the same thing, but as you pointed out have different levels of politeness/formality.
Side note: as far as I'm aware, not using お水 when referring to "drinking water" is not necessarily impolite, but sounds somewhat uncouth.
I'll give a lengthy answer, to help future readers. を (pronounced 'o' when used as a particle) indicates the direct object of the verb. In languages such as German and Russian and Latin, this is known as the accusative case. There is also in English the indirect object (dative case in German etc). In Japanese this is often indicated by 'ni' に.
Consider the sentence: I give the water to the dog. The verb is "give", the subject is "I", the direct object is 'the water' (the water is what is being given) and the indirect object is 'the dog'.
In Japanese and roomaji: 私は犬に水を与えます Watashi wa inu ni mizu o ataemasu.
I've included "watashi wa" for clarity - it is often/usually omitted in Japanese and is inferred by context. "wa" indicates the subject of the verb.
"inu ni" is "to the dog". "ni" is used as "to" for direction of travel and also for indirect objects.
"mizu o" is "the water" with the "o" indicating that the water is receiving the action of the verb (the object), not the the doer of the action (the subject).
PS: There is another particle "e" which is only used for direction of travel. eg "Yokohama e ikimasu" I am going to Yokohama, but you can't say "Inu e mizu o ataemasu" - "e" does not work here.
水 (4 strokes)
Water, flood, fluid, Wednesday
▪Kun: みず(Mizu)、みず- (Mizu-)
•••Words Starting with 水•••
▪ 水曜日《すいようび/Suiyoubi》: Wednesday
▪水道《すいどう/Suidou》: Water service
▪ 水平線 《すいへいせん/ suiheisen》:Horizon
▪ 水割り《みずわり/Mizuwari》: Alcohol
•••Words Ending with 水•••
▪ 香水《こうすい/ Kousui》:Perfume
▪ 淡水《 たんすい/Tansui》:Fresh Water
▪ 海水《かいすい/Kaisui》:Ocean Water
The Japanese sentence is technically a request, and not a question, as you correctly noticed.
I'm not sure why Duo decided to teach it like this, but polite requests in English are also often framed as questions, hence why "to request" is synonymous with "to ask for".
Personally, I do avoid saying direct requests like "please give me that" when I'm trying to be polite in English, because it's essentially a command, albeit a polite one.
This came in handy during my first flight to Japan. I asked for a water please and the flight attendant looked at me quizzically and said Wine? ワイン wain in Japanese. So I said, "お水をください" and she understood immediately! It was a small victory but it was nice to be able to communicate even a little bit.
Actually を is an object marker, indicates the object in the sentence. ください is a polite form of "give," it's an imperative verb. So 水をください= Give water. (Imperative, polite). Basically you omit "to me" because the context is usually clear. You can learn the full phrase "N. + ください" = Please give me N. :)
を marks the direct object of the verb (what the verb is acting on).
In the above sentence, お水をください, を marks 水 (water) as the direct object, i.e. the water is what you want to be given to you.
は is a topic marker. For example, これは水です (this is water/there is no verb acting on anything here).
That's a really interesting question. I definitely don't have a concrete answer for you, but you should be aware that お is only used on certain nouns anyway.
For example, you wouldn't use it on loan words, like おパソコン X ("computer"), and there are many words (usually compound kanji words) which use ご instead.
お and ご are actually just different readings of the same kanji, 御, though, so I'm not sure how "this/that" fits into it.
を is the linking particle used for connecting an object to a verb.
Actually, ください is an conjugated form of the verb 下さる（くださる）which means "to give". The conjugated form ください means "please give (me)". ("Me" is implied by the directionality of 下さる, due to it being kenjougo or humble language)
One thing I've learned practicing these lessons on duolingo is that sometimes the simple answer is the best because it's the most direct translation. We spend so much time trying to construct a complex English sentence from a few Japanese words when in reality, "Water, please" is both accurate AND succinct and the rest of the formalities are just implied. Since the Japanese section is (as of this comment) still in some form of beta, it's been much more useful to boil (ha) everything down to the most basic interpretations and go from there.
You could probably say お野菜をください and お魚をください, but おパン sounds unnatural.
Also, adding お to words like 野菜 and 魚 would make it more polite but it tends to sound feminine for some reason. For certain words, for example お水, おちゃ, おふろ, the addition of お is not seen as feminine, but I'm afraid I can't give you a reason why, and I suspect native speakers will have a hard time explaining it too.
ください is roughly "please give me"; it is a request, asking someone else to give you water. "I want water" isn't really a request, it's simply a statement. Because you want something you might ask for someone to give it to you, but the action of requesting an item or favor is not the same as saying you want it.
"I want water" would be closer to お水が欲しいです using "hoshii" for 'water is wanted/desired'
を is the (direct) object marker, yes. It marks the thing that a verb is acting on. Here the object being given.
The phrase -をください is a humble request with ください meaning "please give me" or "please do for me".
So sentence construction here is (Object) (object marker) (Please give me)
お水 (water) を (object) ください (please give me)
"Please give me water", "Water please", "Can I have/get water"
を is the direct object marker, used with transitive verbs. When a verb does an action TO something you would use wo.
寿司を食べます - sushi (w)o tabemasu - I eat sushi - sushi is the thing being eaten
は is a topic marker. This is used when introducing a new topic and is often dropped if it is understood through context. When you see it think of it as "On the topic of...X" or "About...X". It can also be used to show contrast and in negative sentences. "I do not like X (but I like other things)"
が is the subject particle and stresses what comes before it. The subject is the thing doing/being the verb. Sometimes it is the same thing as the topic, but not always.
これはペンです - kore wa pen desu - This is a pen - "On the topic of this thing - it is a pen" with Pen being the important information about "this thing" kore is a pen, not a different object.
これがぺんです - kore ga pen desu - This is a pen - "This thing (is the thing that is) a pen" with "this" being stressed. This thing is the thing that is a pen, not that thing over there.
私はジョンです - watashi wa John desu - I am John (About me - I am John). John is stressed. This can be shortened to a simple ジョンです if it is already understood you are talking about yourself.
私がジョンです - Watashi ga John desu - "I (am the one who is) John" - "I" is stressed. There are multiple people and you're saying that you are John, not that other person.
(私は)水を飲みます- (watashi wa) mizu wo nomimasu - (I) drink water
私が(水を飲みます) - watashi ga (mizu wo nomimasu) - I am the one (who drinks water)
水をください - mizu wo kudasai - please give (me) water
With both topic and subject:
(私は)水が好きです - (on the topic of me) water (is the thing) I like
お is generally only added to nouns (or verb stems in some grammatical phrases), and even then it's only added to certain words. Some words can use the same kanji (御) but it's pronounced ご instead, and some (most) words simply sound unnatural to have any honorific prefix attached to them.
Would the を particle be placed after a noun as a specifier? To differentiate from any others of the same thing? (Would imply a need for context, like a pointing finger for example...)
I noticed how in the other questions, it would be used to say "This one" or "That one" but here, it's water which is hard to specify as One or Another because of its fluid nature. xD So it threw me off.
This has been answered many times on this discussion thread
を is the direct object particle that marks the thing that is being acted on. Here the action ください is a humble request form of "to give", so the water is the object being given.
寿司を食べます - sushi o tabemasu - (sushi) (object) (eat) - I eat sushi
お茶を飲みます - ocha o nomimasu - (tea) (object) (drink) - I drink tea
本を読みます - hon o yomimasu - (book) (object) (read) - I read a/the book
歌を歌います - uto o utaimasu - (song) (object) (sing) - I sing a song
The words これ、それ、あれ、are the parts that mean "this one", "that one" and "that one over there" in other questions. If you wanted to specify "this water" or "that water" you would use この水、その水、あの水 with この、その、あの being the descriptors of the water.