used to refer to two elements, factors, or people that do not agree or blend together
油和水（指互不相容的因素或人）
help something go smoothly
帮助事情顺利进行
compliments oil the wheels of life.
称赞会使生活更好过。
To bribe
行贿
an attorney who tried to oil the judge's hand in order to obtain a directed verdict favorable to his client.
为使判决导向有利于其委托人的局面而试着向法官行贿的律师
To give a tip to
给…小费
oiled the headwaiter's palm.
给领班小费