1、western United States bird with red undersurface to wings and tail.
美國西部鳥，腹部、翅膀和尾巴為紅色。

2、It provides precise dimensional tolerances, enhanced surface finishes and no undersurface cavities.
該技術可以實現精確的尺寸公差，提高表面拋光度，避免表面下空洞。

3、Large flicker of eastern North America with a red neck and yellow undersurface to wings and tail.
北美洲東部大型金翼啄木鳥，頸紅色，腹部、翅膀和尾巴為黃色。

4、It is worth popularizing as a new type undersurface layer gradation of asphalt pavement.
是一種值得推廣的新型瀝青路面下面層級配。