undistinguishable

The two colors were so undistinguishable that I couldn't tell which was which.

用法提示：此处 undistinguishable 作表语形容词，表示“难以区分的”。

After years of copying, the original painting and the fake became undistinguishable.

用法提示：undistinguishable 描述两者无法分辨的状态，作表语。

The view was so dark that the path was undistinguishable from the forest floor.

用法提示：这里 undistinguishable 与 from 连用，表示“与……无法区分”。