the autumnal equinox

例句：

1. 1. The leaves turned yellow and orange during the autumnal equinox.
   在秋分时，树叶变黄和橙色。
2. 2.This region is famous for its autumnal foliage.
   这个地区以其秋季叶色而闻名。
3. 3. Autumn is a time of transition, with the leaves changing color and the air becoming crisp.
   秋天是一个过渡期，树叶变色，空气变得清新。