1. 煙，蒸汽量在一次呼氣中散發(fā)出的蒸汽、煙霧或類似物質的量
   An amount of vapor, smoke, or similar material released in a puff.
2. 自那時起，從埃及的木乃伊頭發(fā)到石器時代的檀香木等有機物質的年代都已被確定。
   Since then, organic materials ranging from Egyptian mummy hair to Stone Age sandals have been dated.
3. 幻影，幽靈明顯可見但沒有物質的實體；幻影或幽靈
   Something apparently seen but having no physical reality; a phantom or an apparition.
4. 物理學家們正在研究對環(huán)境危害少的發(fā)電新方法，與此同時，許多發(fā)電廠也在實現(xiàn)現(xiàn)代化以減少污染物質的釋放量。
   Physicists are studying new ways of generating electricity with less damage to the environment. In the meantime, many power plants are being modernized to give off less polluting material.

物質的英語翻譯：