gutter fold

例句：

1. 1. The old tree's gulf folds are visible from the roadside.
   从路边可以看到这棵老树的沟渠褶皱。
2. 2. The farmer carefully folded the fabric to keep it from getting creased.
   农民小心翼翼地折叠布料，以免它起皱。
3. 3.The old man's gulf folds were visible in the sunlight.
   老人的沟渠褶皱在阳光照射下清晰可见。