"Push back" without the "on" would have a significantly different meaning. As a verbal phrase, it would mean "return" or perhaps "reject" so ... ... <看更多>

PUSH BACK by Japan Airlines 大家好，我是在成田機場負責引導飛機的相原。今天我要向大家解釋「PUSH BACK（後推）」這個字的意思～ 幾乎所有的飛機開始要出發的時候， ... ... <看更多>

Put Off Put Back Push Back Hold Over Hold Up - Meaning Delay or Postpone - Phrasal Verbshttp://www.iswearenglish.com/ ... ... <看更多>