Naturally occurring magnets aren't powerful enough to lift up huge slabs of steel, but wrap an iron core with wires and run a current through and voila, you can create a powerful electromagnet that can lift cars.
自然产生的磁铁不足以举起巨大的钢板，但用电线包裹铁芯并让电流通过， 瞧，你可以制造一个可以举起汽车的强大电磁铁。