put the boot in treat someone brutally, especially when they are vulnerable. British informal
☞ The literal sense is 'kick someone hard when they are already on the ground'.
英语词组固定搭配大全包含15956条英汉双解词组,基本涵盖了全部常用英文词组、短语的翻译及用法,是英语学习的有利工具。