这是一个源于拳击运动的表达。在拳击时 pull your punches 意思是出拳有所保留，手下留情，不伤到对手。现实生活中，人们用这个短语来形容对他人的批评有所保留，不伤到对方的自尊心。这个短语往往以否定形式出现，以表达“不要留情面”。
例句
The report didn’t pull any punches in its criticism of the journalists' behaviour.
I don’t want you to pull any punches. Tell me honestly what you thought of my essay.
请注意
如果什么东西 packs a punch，意思就是力度大、有冲击力，效果强烈。
例句
Wow, that cocktail really packs a punch. How much vodka did you put in?
His photos really pack a punch. They graphically capture the horror and misery of war.
