(informal)when (or before) the action or trouble starts(非正式)行动(或麻烦)开始(之前)
英语六级真题
James hiked, fished, learnt to sail and experimented with hot air ballooning.
出自-2013年12月听力原文
柯林斯高阶英汉双解学习词典释义
N-COUNT
气球
A balloon is a small, thin, rubber bag that you blow air into so that it becomes larger and rounder or longer. Balloons are used as toys or decorations.