"My mother and father are fine."
While I'm generally keen on learning "idiomatic" translations, and maybe this English sentence and that Japanese sentence reflect the difference in what's idiomatic in each language, in this case it would make sense to have the English be (something like) Both my father and mother are well (or …are both well), because it would reinforce the meaning of the different grammar better.
(I'm finding the en -> fr course annoying for the opposite reason, it's sometimes very insistent upon such "strictly matching" translation :o)).
Just had this come up again, and I'm still annoyed that they aren't giving the English sentence as either Both my mother and my father are well or My mother and my father are both well (the former would be preferable for matching the meaning of the Japanese grammar here).
"も" replaces "を" and "は" as particles, so there shouldn't be a "は" after the second "も". in this case, when there are two "も" you should think of it more as a set phrase, like "as well as".
"も。。。も。。。"basically means "as well as" or maybe "both" . So: "My father, as well as my mother, are fine." another example: "田中さんも私も学生です。= "both Tanaka and I are students." also works the other way around: "田中さんも私も学生ではありません。" = neither Tanaka nor I are students."
I understand the meaning of "も" and "と" , but I still think the English sentence should be "both my father and mother are fine" or "my father and my mother are both fine" so we can use the "も" correctly with its exact meaning ("also", "as well as", etc.) rather than just an "and"