"When did they write a letter?"

Translation: Când au scris ei o scrisoare?

[DavidRomanH]

Can someone please explain why this is a wrong answer: Când ei au scris o scrisoare

[Anna507049]

It is correct. This app is sometimes a mess.

[AnninaPR]

This app is most of the time a mess.

[Andra_Iasomie]

It sounds like you are saying "When they wrote a letter..." and that you will continue the sentence instead of ask "When did they write a letter?"

[GlennEvani]

99% of the time, Duo does not invert for questions. 1% of the time, it marks you wrong unless you do. This is an example of the 1%.