"The cold pierces me to the marrow" is an idiom in English. "The cold pierces me" isn't an idiom, and isn't a literal translation of "téann an fuacht tríom" either, so it's not a good translation.
If you got this sentence as a "pick the words" exercise, it's usually only based on a single preferred translation.
I'm a native English speaker (US) and I've never heard "the cold pierces me to the marrow" but I /have/ heard "the cold goes [right] through me" so I'd prefer having the proper translation in the software as there's nothing about piercing or marrow in the Irish.
And, yes, idioms can be challenging because they're cultural so I wonder what English-speaking culture says "the cold pierces me to the marrow"?
I totally agree with gksmithlcw. I'm from the US (300 years of family in New England where the winters are pretty darn cold) and I've never heard anyone say the cold pierces them to the marrow, with the possible exception of a recitation of some impossibly flowery piece of poetry, or in the lyrics to a song. When it's too cold to snow and the snow that is already lying about on the ground the squeaks underfoot and you literally cannot breathe without having your face wrapped in a scarf, "The cold goes (right) through" a person.
It's not an idiom that I'd ever use, but I'd recognize it if I heard someone else use it. I don't know how the sentences in Duolingo were developed, or whether this one started out in English, and was translated to Irish, or vice versa, but there are always going to be issues with translating idiomatic speech - you just have to treat them as "teachable moments".
For what it's worth, I'd typically say "That wind would cut through you", using a conditional (it would if it could!) rather than a habitual present.
I also agree. As a Native Californian, I say the cold goes right through me. I tried an amalgamation of the two - The cold pierces through me, hahah and got it wrong. I've also heard the cold cuts to the bone. Any of these, I think, convey the same message, and should be accepted. And even though I know what duo lingo wants me to say - sometimes I try a variation to see if translates - and with this idiom, I guess it doesn't.
Ireland has it's own special brand of "wet cold" that penetrates your many layers of clothing and "goes" or "cuts" into your bones. Other, colder countries (such as Norway) have a "dry cold" that only seems to make it to your skin, even if the temperature is lower. Of course this is only my own experience of it, but you can never get warm after being cut through by an Irish wind! :)
I can think of a dozen different idioms that mean "I am freezing", even leaving out the versions that contain profanity. It's not really practical to list them all. But this particular phrase emphasizes the movement of the cold into or through a person, not just the state of being cold - táim sioctha! is a fairer rendition of "I am freezing!"
I would argue that if the translation is to be a very colloquial idiom they should have thought about more than just one. For example I have never heard of "pierce to the marrow" But I have heard "cut to the bone", "cut to the quick" and "pierces through". The last one being a much closer translation of the sentence to the one Duolingo demands.
I love this discussion. As an Australian I would say- the cold goes through me or chilled me to the bone (if I was being literary) or just- I'm freezing. "cold pierces me to the marrow" sounds like Shakespeare. It would be expecting a lot for a computer to cope with all these variants.