obstruction

n.妨碍；障碍物

obsession, obsessional, obsessive, obsessively, obsolescence, obsolescent, obsolete, obssess, obstacle, obstacle race, obstetric, obstetrician, obstetrics, obstinacy, obstinate, obstinately, obstreperous, obstreperously, obstreperousness, obstruct, obstructionism, obstructionist, obstructive, obstructively, obtain, obtainable, obtrude, obtrusion, obtrusive, obtrusive-ness, obtrusively, obtuse, obtuse angle, obtusely, obtuseness, obverse, obviate, obvious, obviously, obviousness,