短语词组短语back -burner 不重要的back wall of burner 小炉后墙on the back burner 搁在靠后的炉子上；搁置着put on the back burner 先搁置一边;缓议;暂时搁置一旁;把back and forth type burner 往复式燃烧炉 返回 back burner