Since magnetic forces travel poorly through air, the electromagnet has metal shoes that fit close to the poles of the permanent magnet.
(magnetic forces; travel; poorly) (the electromagnet; has; metal shoes that fit close to the poles of the permanent magnet) (metal shoes; fit; L:close to the poles of the permanent magnet)
magnetic forces the electromagnet metal shoes
travel has fit
poorly
metal shoes that fit close to the poles of the permanent magnet
L:close to the poles of the permanent magnet