Student or Learner
Barcelona has changed out of all recognition.
I couldn't catch the meaning, could you pls enlighten me?
It means that the city has changed so much that people are unable to recognize it.
Here is the explanation from the online version of the Macmillan Dictionary:
beyond/out of (all) recognition
in a way that makes it impossible to recognize who someone is or what something is
Many of the bodies were burned beyond all recognition.
Family life has changed out of all recognition in the space of a few generations.
I hope that helps.
Have a nice day. :)