Translation:Mrs. Tanaka is good at playing tennis.
It's the same as the English gerund (put -ing at the end of a verb to turn it into a noun/activity: swim > swimming. Sing > singing). You can do a similar thing with (~する)こと, but (~する)のが is easier to use.
(Caps and katakana for emphasis) I like playING tennis (私は)テニスをするノガ好きです。
I like eatING (私は)食べるノガ好きです。
Not an error. Miss and Mrs. both imply that you know the marital status of the woman in question.
We are still brought back to the point in the top comment. We know nothing about Tanaka, including Tanaka's gender, marital status, and other details.
さん is both Mr. and Ms. The only way to know is if the name is a boy or girl name or through context.
The "playing" part should be correct. In the other question they corrected that.
Tanaka information thread -good at tennis -mother is likely to be a teacher -gender unknown
Sounds good enough? In general, click that flag button if you're rather positive you were correct.
I dropped the Mr. because it is a gender neutral name. Why would that be wrong?
Adding さん conveys a degree of formality, which in English is normally translated to a title such as Mr. or Miss. (Dr. is a gray area, but most often it would be 先生 (せんせい). )
Dropping Mr. would also mean dropping さん or replacing it with something less formal such as くん or ちゃん.
Actually, -san is not always translatable in English. English speakers usually do not address their peers as "Mr. So-and-so" or "Ms. So-and-so". This is especially true among students. After having spent nearly half of my life in Japan, I suggest that it's best just to leave "-san" as is. Everybody who knows me here in Japan calls me "Wolk-san", not "Mr. Wolk", even when we are communicating in English. And I address them as "~san".
Tanaka is a surname, though, not a gender-neutral name, except in the sense that Japanese surnames don't vary for gender. In English, you normally can't use a surname without something in front of it, so I'd say you would need a Mr/Mrs/Ms/Miss in front of Tanaka, or leaving the -san in the English
Actually, English-speaking people use a surname without a title quite frequently. That is especially true of boys and men, who refer to each other by just their last name all the time. No boy ever called me by my first name in junior high or high school (unless they were asking for me on the phone), and I doubt that you will ever hear high school students calling each other "Mr." and "Ms", unlike in Japan, where everyone is a "~san", or occasionally "~kun". Teachers are always addressed as "~Sensei", never "~san".
"Mrs. Tanaka" would usually be expressed by an adult as Tanaka-fujin (田中夫人) if they want to emphasize the "Mrs" part. However, kids usually address the parents of other kids by their parental title, such as Tanaka-okaasan 田中お母さん or Tanaka-otousan 田中お父さん.
Your answer is not wrong. I think the problem here is, Duo doesn't recognize the Kanji 上手 for "じょうず", just like it sometimes doesn't recognize the Kanji 達 for ~たち
The issue was if I remember correctly an answer using "Mrs Tanaka" was marked "incorrect".
So, I would have phrased this sentence 田中さんはテニスが上手です。is that the same meaning, or is there a different connotation?