短语词组短語back -burner 不重要的back wall of burner 小爐後牆on the back burner 擱在靠後的爐子上；擱置著put on the back burner 先擱置一邊;緩議;暫時擱置一旁;把back and forth type burner 往複式燃燒爐 返回 back burner