He thrashes around as if fighting the bedclothes.

他会在床上乱动，好像在与床单搏斗；

He carries the wheat to his barn, and there he thrashes it, or beats all the grains of corn out of the ears.

农民将麦子运到谷仓并打谷, 也就是将谷粒从麦穗中敲打出来。