log·roll /ˈlɔgˌrol, ˈlɑg-/
  (vi.)滾木材,互助,合作(vt.)互投贊成票使通過
  Log·roll v. i. & t. To engage in logrolling; to accomplish by logrolling. [Political cant, U. S.]
  ◄ ►
  logroll
       v : work toward the passage of some legislation by exchanging
           political favors such as trading votes