骑马者用靴刺戳了戳马的侧腹.The rider dug his spurs into the horse's flank.他用靴刺刺马的侧腹.He dug his spurs in the horse's flanks....

“侧腹”的英语可以翻译为：flank ...

“侧腹片”的英语可以翻译为：laterosternite，pleurosternite ...