Disease is not likely to be the most important factor in whether the world's population will spike. Drought and ignorance are much more likely candidates.
疾病似乎并不是影响世界人口是否激增的主要因素，而干旱和无知更像是潜在原因。
2
The first and perhaps key factor is the ignorance of sanitation.
第一个也是最重要的一个因素是人们缺乏卫生意识。
3
And ignorance to universal existence of transaction cost covers the essence of problem and makes us missing the key factor of empirical analysis.