Translation:I do not play tennis on rainy days.
This is what I was referring to with the original comment. I guess "days" is accepted if you get this sentence as a "type your own answer" question, but when it appears as a "pick the words from the list" question it doesn't give the plural option—but it really should, as that should be the default translation rather than the singular version.
I think I might be inclined to use やる in the passive voice in this case, because するsounds a bit weird here... Passive would be やられません. やる is just another word for "to do." (and a couple of other meanings... Be careful not to use it with people...)
As is the case with many literal translations, there are better ways to make the nuance sound more natural. You could stick with the original sentence 「雨の日は、テニスをしません。」, and imply a subject of "people in general." Then you would get the passive sense. Kind of cheating your way around it, but that's fine.
OR, I might want to say, "Tennis isn't played in the rain, because the rain ruins everything and it's just too hard." In which case a simple 「雨の日は、テニスができません。」 would be perfect. ("Tennis can't be played on rainy days.")
できる（できます）is the "able to" form of する。
Good food for thought! Thanks for the discussion.
Thanks for your example. So is the difference that "する" is being used in a passive voice? What makes it unnatural / how would the following translation then go, in your opinion?
A: "Why isn't anyone playing tennis?" B: "It's raining. Tennis isn't played on rainy days"
Edit: Found a decent resource which helped clarify the translation: http://www.guidetojapanese.org/learn/grammar/in-transitive
You used が in your reply, which is correct, but since を was used in the original sentence, that implies a transitive verb; I.e. Someone/Something is "doing" the verb. Whereas が and されて indicate that the verb is "happening" without the direct involvement of an agent. Can't speak for whether it's a natural sentence or not, but the article in the link + your example definitely help identify how you would distinguish a sentence with an implied subject vs one that intends to use an intransitive verb.
Imperative would be 「テニスをしないで」, usually with 「ください」 at the end unless you're speaking to someone of lower status (i.e., a child), or 「テニスをするな」 for a really strong command (i.e., angrily shouting at a misbehaving child). On the 2nd point, it could certainly be a general statement as IsaiahGaff suggested, but without further context I would never translate this with another subject. In a sense, the lack of context is precisely what implies that it's the speaker—we haven't been given any information to suggest that it's someone else, so translating it as such would be unjustified.
There is no specified subject in the japanese sentence. With no context to go off of, expecting a specific subject in the english translation is unreasonable.
For example "On rainy days, we don't play tennis." was considered incorrect, only because of the subject "we" instead of "I"
Yeah the verb that is normally paired with tennis is "play". Honestly it doesn't sound unnatural, but I think it's got a different nuance / feeling.
Like, you could say, "I don't do movies" vs "I don't watch movies". "Watch" is definitely more normal / literal. But saying "I don't do movies" is kind of like saying "I am averse to an activity that involves 'movies'". More of a "feeling".
It's also more broad of a meaning, because a retired filmmaker could say both, "I don't make movies anymore" or "I don't do movies anymore". Whereas for someone else "do" might mean watch, film, edit, record, etc. So using a more specific verb gives more context.
Well in that sense "do tennis" can answer many questions, probably as you stated in the negative "don't do". The positive most likely is "do do" as in "do do tennis"
Do you play tennis? I don't do tennis. ("don't play" is a more natural answer)
Do you organize tennis tournaments? I don't do tennis
Do you sell tennis rackets? I sell other sporting equipment. I don't do tennis
Do you make tennis documentaries? I don't do tennis
Do you (insert the rest of a sentence involving tennis)? I do do tennis
Good questions! Question #1: Once you introduce a subject using 「は」、you don't need to use the subject again. The context is understood. The issue is that in Duolingo, we have single sentences out of context. So we don't know if this sentence is actually "I," "you," "Bob," "Everybody in the school," etc . So here we can guess わたし, but if you used he or she or we or you or they, those should all be correct. Hit the report button if it doesn't work.
As to why this is not a command ("Don't play tennis,") the negative command form is made by putting the verb into plain negative form （しない, in this case）and adding で --> しないで。And then you can add a ください if you would like to make it more polite。
Hope this helps!
As far as I'm aware, a literal translation would be something like: "With respect to rainy days, [something / someone] does not do tennis". Nothing about this sentence directly means "play", except that that's the verb of choice in English. します is the polite, "masu" form of the verb する, which is very general & means "do" among other things.
There isn't an explicit "subject" listed here, but it's probably supposed to be assumed from preexisting context. "I/they/he/she/we/etc don't play tennis on rainy days". I think it could also be taken to mean more generally, "Tennis isn't played on rainy days" depending on the nature of the previous conversation.
The other thing of note, which I'm honestly still not sure of, is "transitive / intransitive" verbs & what affect this has on the sentence's meaning. Since this sentence uses an を character to connect "tennis" and "do", that means tennis is the direct object of the verb & "suru" here is "transitive". What we glean from that, I'm not sure.
Re: transitive verbs and する, while ～をする does literally mean "to do [something]", this is the standard way of saying "play [a sport]" in Japanese. As such, I think the appropriate translation would in fact be "play tennis" rather than "do tennis".
There are different verbs used for the other contexts where we use the verb "play" in English, such as a child playing (あそぶ) or playing an instrument (～をひく).
Japanese has it's own comma, and the usage seems pretty liberal. It's probably worthwhile that Duo put it in a sentence or two:
'Comma usage in Japanese is incredibly liberal compared to English. You can stick it pretty much wherever you want a break or pause in your sentence.' https://www.tofugu.com/japanese/japanese-punctuation/
'The symbol “、” is called 読点 (とうてん). It is used to denote a semantic separation or a pause. Compared to comma in English, the usage of 読点 in Japanese is less governed by the grammatical rules. In other words, in Japanese, the author is free to use or not to use 読点 in any place where a separation makes sense.' https://japanese.stackexchange.com/questions/3786/usage-of-commas-in-japanese-sentences