词根:grad = step, grade, 表示“步, 级”
grade n. 等级,阶级
gradient a. 步行的n. 坡度(grad+ient)
gradation n. 等级;层次(grad+ation)
gradual a. 逐步的(grad+ual)
graduate v. 毕业;分级(grade 步+uate→完成所有步骤→毕业)
graduation n. 毕业(graduate+ion)
degrade v. 降级;退化(de向下+grade→向下降级)
degrading a. 不名誉的,可耻的(de+grad+ing→向下降了→不名誉的)
retrograde v. 退步;堕落(retro向后+grade→向后退步)
upgrade v. 上升,升级(up向上+grade→向上升级)
downgrade v. 贬低,降低(down向下→ grade→向下贬低)
centigrade a. 百分度的( centi百+grade级,度)