Fourtou富尔图fournum.四four-strand double crossing over四线双交换four-lane section highway tunnel4车道公路隧道four-layer security architecture四层安全体系结构four thousand four hundred and two(=4402) 四千四百零二four thousand six hundred and four(=4604) 四千六百零四Four stages water level adjustment四段水位调整four- row tapered roller bearing四列圆锥滚子轴承Fourier transform infrared spectra傅里叶变换红外光谱four thousand nine hundred and one(=4901) 四千九百零一four thousand one hundred and five(=4105) 四千一百零五