border on

verb

(transitive) To share a border with. / (transitive, figuratively) To be almost like some other thing; to verge on.

The United States borders on Canada.

意味（1）

(transitive) To share a border with.

The town borders on the forest, so there are often deer on the road.

意味（2）

(transitive, figuratively) To be almost like some other thing; to verge on.

His behaviour borders on insanity.