Kindly, consider the following situation:
The question says: Complete the following with was / wasn’t able to.
The context says: A man said: ‘In my garden, there is a heavy stone, I tried to lift it many times when I was young, but I couldn’t move it. And when I grew old, I still wasn’t able to lift it. Nothing has changed!’
Is this use of 'still wasn't able to' correct? Shouldn't the context be: 'still unable to'?
Thanks in advance.