资源介绍：学案比较符合学生特点，较为实用，获得了学生的认可。

1.quality n. (U) 质量   (和quantity数量相对)
The changes of quantity cause the changes of quality.
             We aim at quality rather than quantity.
          (C) (人的)品质 ,性质, 特性
             Tom has all the qualities of a great man
             One quality of wood is that it can burn.
2.mean  adj 吝啬的  （generous） be mean with money.
           自私的   selfish→反义词  selfless
           卑鄙的 ，刻薄的    be mean to sb
         v.  意思，意味着，打算mean to do╱mean doing
                               A dictionary tells you what words mean.