Tbe change of fertility was a process of quantitative alteration to qualitativealteration.
结果表明：育性转换是一个量变到质变的过程。
2
Even the difference of musical notes may be regarded as an example of what takes place in the process of measure the revulsion from what is at first merely quantitative into qualitativealteration.
音调的差别也可认为是尺度的变化过程中发生的，由最初单纯的量变到质变的转化过程的一个例证。
3
This article mainly adopts qualitative and quantitative analysis, theory and demonstration analysis to study the alteration of natural gas price.