paper的复数形式
paper作“纸张”时，不可数； 例：We cut down trees to make houses, furniture and paper. paper作“报纸、试卷、论文”时，可数，papers表复数。 例：We shall go through these papers together...
paper作“纸张”时，不可数； 例：We cut down trees to make houses, furniture and paper. paper作“报纸、试卷、论文”时，可数，papers表复数。 例：We shall go through these papers together...