Unfortunately, as a standard mattress wears, the springs soften and so do not support your spine...遗憾的是，当一张标准床垫用旧后，弹簧就会变软而无法支撑你的脊椎。The bed-springs creaked.床垫的弹簧嘎吱作响。Ferroalloy and Products, Springs and Coils, Cold, Hot, ...
把它们相加再除以5就是平均数，明白吗？Add them together, divide by five, and you've got the average. Okay?量一下温室的建筑面积再将它除以6。Measure the floor area of the greenhouse and divide it by six.230厘米除以22厘米等于10.45厘米。230cm divided by 22cm is 10....