    Sentence 4: Attackers detonated a second  roadside bomb later Sunday as a U.S.  convoy was traveling near Fallujah , killing  lan American soldier and wounding three  others .    Sentence 2: Attackers detonated a second  roadside bomb later yesterday as a U.S.  convoy was travelling near Falluja , just  west of Baghdad , killing an U.S. soldier  and wounding three others .