后墙...

The quality of freeway structure retailing backwall refilling concerns the freeway global quality.高速公路构造物台背回填质量关系到高速公路整体质量....

backwall的音标：backwall的英式发音音标为：[bæk'wɔ:l]backwall的美式发音音标为：[bæk'wɔl]...