When I grow up, I'll be an astronaut.
When I grow up, I'm going to be an astronaut.
We've been staying with Paul and Jenny until last weekend.
We were staying with Paul and Jenny until last weekend.
I was meeting a lot of interesting people while I was working in Norway.
I met a lot of interesting people while I was working in Norway.
I know Paul for 5 years.
I have known Paul for 5 years.
