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to be surprised; to be amazed; to be frightened; to be astonished; to get startled; to jump
surprise (e.g. surprise party)
突然の訪問にびっくりした。
I was surprised by the sudden visit.
びっくりして声が出なかった。
I was so surprised I couldn't speak.
びっくり箱を開けた。
I opened the jack-in-the-box.