— Here you are at last! Where have you been?
— I’ve been fishing. I’ve caught a big fish.
— What fish did you catch?
— I caught a salmon.
— Where were you when you caught it? (Or should it be "Where have you been when you caught it"? Or both are correct? My teacher suggested to me this option but I'm not sure if it's right)
— I was at the lake. (or I’ve been at the lake?)