Describing Change Over Time
"Yes, it's changed a lot" is true of almost everything, which is exactly why it's a weak answer - it gives the examiner nothing to picture. This page shows you how to paint a quick before-and-after picture and show how big the change actually was.
This is the quick-fix version — see the full guide →When "it has changed a lot" is all you say
"Why doesn't 'Yes, it has changed a lot' get me a good score?"
It's true, but it's just a headline - the examiner wants an actual picture of what it used to be like and what it's like now, so follow it with one specific detail.
Painting the "before" picture, not just "now"
"How do I compare 'then' and 'now' instead of just describing today?"
Give two little pictures, not one - say what it used to be like (past simple or "used to") and then what it's like now (present simple), right next to each other, so the change is obvious.
Showing how big the change was
"How do I show how much something has changed, not just that it changed?"
Add a comparative adjective after your before/after picture - "much bigger", "a lot more crowded" - to show the size of the change, not just the fact of it.