On a January day in 1921, a middle-aged Negro man sat in a room of the Capitol Building in Washington, D.C., waiting to testify before an important congressional committee charged with setting tariffs on agricultural products.是什么意思_On a January day in 1921, a middle-aged Negro man sat in a room of the Capitol Building in Washington, D.C., waiting to testify before an important congressional committee charged with setting tariffs on agricultural products.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句