seeI can see for miles from up here.
noticeI noticed a crack in the ceiling.
perceiveBill perceived a tiny figure in the distance.
observeformalA teacher observed her climbing over the gate.
spotWe managed to spot a leopard.
catch sight ofWe looked for the bird and caught sight of it just as it flew off.
catch a glimpse ofHe caught a glimpse of his reflection in the glass.
glimpseI glimpsed her as she ducked round the corner.
make outI could just make out a figure standing in the doorway.
clap/lay/set eyes onI've never laid eyes on him before.