Isn't more correct translation "it is getting cloudy"?
In English, the expressions "to cloud up" and "to get cloudy" mean the same thing, so both should be accepted. Not in the form you just wrote, though.
Cloud up? I've never heard anyone say that. In England, it's always 'cloud over'.
Agreed, we never say to cloud up. We say to cloud over or to get cloudy.
Dear Duo, I think that you should change the Romanian-English dictionary you are using for a more reliable one
In American English, I'd use "getting cloudy."
We might say that a window or mirror 'clouds up'.
What about 'to ignore'?
it's not reflexive