To all three of you, the reason why some of the previous cities didn't have an English translation is because there are no English translations. If there is an English translation, this lesson wants you to use it. That's why "Caergybi" is wrong. If there were no English translation, it would be right. Edit: I was just going off what the tips and notes said, but clearly I shouldn't have because I am ignorant about this subject compared to the rest of you. I do apologize for offending anyone and I thank you for your patient and thorough explanation of the subject matter. One question remains, however: If there is a so-called "English translation" of a place, why would you not use it?
If you had read the original response before shouting, you would have noticed that its the lack of consistency through multiples of the questions in Places1, not the fact that this one question triggers the response.
You would also come to find that sometimes (and with no way of knowing) the Welsh name is accepted in spite of there being an English version.
I personally just used the Welsh version with every response in the training unit, unless it wouldn't let me, because I don't care as part of learning the Welsh language. I will deal with what name I choose to use in a real life situation based on the person I'm speaking with, just like I do in Czech or Germany (Munich vs. Munchen as an example).
Though I do get a chuckle out of the idea that there is a "translation" for New York, and I get that York did exist as a translated name before New York was founded, it's still humorous to me.