It's the same in German, btw. Fridge = Kühlschrank. Kühl = cool/cold, Schrank = cabinet, wardrobe.
not sure about tủ, but lạnh is indeed a Sino-Vietnamese word, except that it's from 冷 not 凍.
yes my Vietnamese gf says ok you can do duolingo if it is fun for you but to speak the language you need to learn useful conversation. The problem is that without duolingo I don't learn anything and she still doesn't help me at all. But of course she wants constant help with English. Why is that?
Duo owl, you are cái máy/ tủ lạnh/ mây/ con mèo / con gấu...are you sure this is not DID?