obstacle
n
(usu fig 通常作比喻) thing in the way that either stops progress or makes it difficult 障碍; 妨害物
obstacles on the race-course 赛马跑道上设置的障碍物
obstacles to world peace 世界和平的障碍
Not being able to pass his mathematics exam proved an obstacle to his career. 他数学考试不及格是他前途上的一大障碍.