Pole vaulters have to clear or get over a bar held by two posts without knocking the bar down, then land safely on a foam filled mat.是什么意思_Pole vaulters have to clear or get over a bar held by two posts without knocking the bar down, then land safely on a foam filled mat.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句