C 障碍（物），妨碍sth which prevents action, movement, or success

　clear away〔remove〕 ～s　排除障碍
　come across〔encounter, meet〕 an ～　遇到障碍
　constitute〔overcome, take〕 ～s　构成〔克服，越过〕障碍
　install an ～　设置障碍
　overleap ～s　越过障碍物
　chief ～　主要障碍
　natural ～　天然障碍
　serious ～　严重的障碍
　tremendous ～　巨大的障碍
　unexpected ～　没预料到的障碍
　～ course　障碍赛跑训练场
　～ race　障碍赛跑
　amid many ～s　许多障碍之中
　all kinds of ～s　各种阻碍
　～ to　对…的障碍

　The huge tree that had been blown down by the storm was an obstacle to traffic.　被风暴刮倒的大树是交通的障碍。
　Lack of education is an obstacle to success.　缺乏教育是成功的障碍。
　When short waves are sent out and meet an obstacle, they are reflected.　短波发出后，遇到障碍物就反射回来。
　She felt that her family was an obstacle to her work.　她感到她的家庭妨碍她的工作。

　［同义词］ bar, block, limitation, obstruction
　［反义词］ aid, expedient, help, support
　［词源］拉丁语obstaculum