Reconstructed Incan terraces and buildings show the skilled stonework for which the ancient people are celebrated.秘鲁图片集.重建的印加梯田和建筑物显示熟练的技术的石匠,其中古代人是著名的....
他测出了超声波穿过骨头的速度。He measured the speed at which ultrasonic waves travel along the bone.超声波扫描显示她怀了双胞胎。Ultrasound showed she was expecting twins.大多数处于妊娠期的妇女将被建议接受超声波检查，不过这不是强制性的。Most women will be offered an ultrasound scan ...