短语词组短語doubtful of about 懷疑doubtful view about ancient history 疑古史觀be doubtful about 對;疑惑的remaining doubtful about sth 半信半疑地were doubtful about 從第三段意思可知“因爲她是一個對辳業沒有任何經騐的大學生I am doubtful about that 我對此表示懷疑 返回 doubtful about