dig/dip into (your) pocket
to use your own money to pay for something.
Parents of young children have to dig deep into their pockets at Christmas-time.
英语词组固定搭配大全包含18674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。