unbridgeable a不能架桥的
To dig an unbridgeable river掘了一条无法跨越的沟渠
ADJ（形容词） An unbridgeable gap or divide between two sides in an argument is so great that the two sides seem unlikely ever to agree. 不可逾越的; 不能同意的 [journalism]
...the so-called unbridgeable gap between the world of humans and that of chimpanzees.
...人类社会和黑猩猩社会间所谓的不可逾越的鸿沟。