In the meeting, she remained quiet and withdrawn, not participating in the discussion.

withdrawn 是动词 withdraw 的过去分词形式，withdraw 由前缀 with-（表示"向后、离开"）和 draw（"拉、拖"）组成，本义是"撤回、收回"。 在这里 withdrawn 作为形容词使用，描述一种内向、不愿与人接触的性格状态，意思是"孤僻的、沉默寡言的"。