名词
中文翻译：上螺旋线
同义词：
['upper spiral line', 'upper spiral boundary例句：1. The upper spiral line is the boundary between the two plates.（上螺旋线是两个板块之间的边界。）']
例句：
-
1. The upper spiral line is the boundary between the two plates.
上螺旋线是两个板块之间的边界。
-
2.The upper spiral line is crucial for the stability of the structure.
上螺旋线对于结构的稳定性至关重要。
-
3.The upper spiral line was used to mark the location of the new tunnel.
上螺旋线被用来标记新隧道的位置。