'Haben Insekten eine Lunge?'
This sentence in the German Body 2 skill is mistranslated as 'Do insects have a lung?' but there's no way to report it. If you click on the report button, there's only three options, and none of them are to report an unnatural English sentence.
I've noticed that a lot - why does it happen?
This is the discussion on that sentence: https://forum.duolingo.com/comment/11107946
For the reasons I wrote above.
But also bear this in mind: 'Eine Lunge' doesn't just mean 'a lung', it means 'lungs' or 'a pair of lungs', too.
Imagine a picture of some people. Each person is wearing a hat. Which sentence is correct?
- The people have hats.
- The people have a hat.
Imagine a language in which there were no plurals and the literal translation of the equivalent sentence is 'The people have (a) hat.' But it's the same picture - multiple people, multiple hats. The correct English translation would still be 'The people have hats', even if you could form a grammatically correct, word-for-word translation from the sentence in the other language.
Additionally, very few animals have a single lung - some snakes, the lungfish. The vast majority of animals have two lungs.
Do mammals have lungs? Yes, they do.
Do mammals have a lung? No - they have two lungs. Each.