Addison witulski's grandmother kim Allred said Addison probably overheard a conversation between family members talking about the funds needed to get her little brother to treatment.
2017年12月四级真题（第二套）听力 Section A
柯林斯高阶英汉双解学习词典释义
VERB
偶然听到；无意中听到；偷听到
If you overhear someone, you hear what they are saying when they are not talking to you and they do not know that you are listening.