apical initial

例句：

1. 1. Theapex of the mountain is wherethe sun rises and sets.
   山顶是太阳升起和落下的地方。
2. 2. The apex of the archwas made from marble.
   拱顶是用大理石制成的。
3. 3. The apex ofthe pyramid is the highest point.
   金字塔的顶端是最高点。