Their mating calls left no room for doubt.他们求爱的呼声不容置疑.The male bird performs a sort of mating dance before copulating with the female.这种雄鸟在与雌鸟交尾以前要跳一种交欢舞.I thought you were giving up on the mating dance.我以为你们俩己经放弃不继续跳这段求...
撕裂的肌肉会收缩，丧失原来的力量、结构和紧实度。Torn muscles retract, and lose strength, structure, and tightness.通过胃部肌肉的收缩食物和流质在胃中混合。Foods and fluids are mixed in the stomach by its muscular contractions.这种疼痛是由于血管的收缩而引起的。The pain is produced b...