When I was training for my PPL at Cambridge one day about 5 years ago and doing circuits, somebody called as being ahead of me and on final. I couldn't see him from base leg and still couldn't see him when I turned final .... although believe me I was looking very hard by this time.
I asked the tower where the previous was and she said she was uncertain and didn't have him in sight so I elected to go round.
She asked again where he was and he said on the ground, runway vacated and would like taxi instructions for parking.
She said WHERE on the ground as she couldn't see him.
In front of the museum he said.
Resounding crash of pennies dropping and she said .. in that case I suggest you call DUXFORD on 122.075 for your taxi instructions.