Brought about by the constantpressure of lying on a stationary surface, painful ulcers can involve substantial skin loss, sometimes exposing muscle and even bone.
由于躺在静止的平面上持续产生的压力，疼痛性溃疡会伴随大面积皮肤脱落，有时露出肌肉，甚至骨头。
2
Air pressure on the surface of the Earth is fairly constant, so in designing a microphone for use on land, engineers don't have to worry about large variations in air pressure.
地球表面的气压相对稳定，因此设计地面用的传音器，工程师并不需烦恼气压的大幅变化。
3
While the pressure difference between the inlet of fracture and the outlet of fracture is constant, the transmissibility of fracture surface will decrease with the rising fractal dimension.