考研英语

oak oar oath obedience obedient obey object objection objective obligation oblige obscure observation observe obsession obsolete obstacle obstruct obstruction obvious occasion occasional occupation occupy occur october odd odds odor offend offensive offer officer offset offspring oil oneself onion opaque opening opera operate operation operational operator opinion opponent opportunity oppose oppress opt optical optimistic optimum option optional oral orange orbit orchard order orderly ordinary ore organ organic organism organization organize orient oriental orientation origin original originate ornament orphan orthodox ounce outbreak outcome outdoor outer outfit outlet outline outlook outrage outset outskirts outward oval oven overcoat overcome overflow overhear overlap overlook overnight overseas overtake overthrow overtime overturn overwhelm overwhelming owe owing owl owner ownership ox oxide oxygen ozone