The Brainliest Answer!
People are surprised when they meet someone after a long time without even a prior notice. they are surprised when they are gifted a present without any knowledge. so actually it means that someone is surprised when some thing good happens with some one the person is surprised.

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2 4 2
People sometime get suprised to see someone whom u are meeting aftr a long time or u get surprised to see some precious thing of urs which u were searching for.

plz mark my answer as brainliest