To see someone or something very briefly or suddenly.
突然地，粗略地看到某人或某物
I didn't so much as catch sight of him all day long.
我一整天都没见他人影。
I walked slowly, casually, hoping she would catch sight of me.
我装作满不在乎地款款而行，希望她会一眼看到我。
Keep looking up, and you may catch sight of some unexpected creatures.
继续观察下去，说不定会看到意想不到的动物。
