decrease: suggests a progressive decline in size, amount, numbers, or intensity: slowly ~d the amount of pressure.  decline是降低的基础词=lower


lessen: suggests a decline in amount rather than in number: has been unable to ~ her debt at all.  数目number指某一事物的个数


diminish: emphasizes a perceptible loss and implies its subtraction from a total: his muscular strength has ~ed with age.  (perceptible可感知察觉applies to what can be discerned, often to a minimum extent, by the senses尤指最小程度上，如a perceptible difference in sound声音有微弱/可觉察到的差别)


reduce: implies a bringing down or lowering: ~ your caloric intake.


abate: implies a reducing of something excessive or oppressive in force or amount: voted to ~ the tax.


dwindle: implies a progressive lessening and is applied to things capable of growing visibly smaller or disappearing: their provisions ~d slowly but surely.  供给供应


decrease减少减小: 指逐渐降低，用于尺寸数量数目强度等，lessen减少: 用于数量而非数目，diminish减少: 强调稍微减少(也就是逐渐)，使总量降低，reduce减少: 泛指降低，abate减少: 指减少过度令人压抑的事物，dwindle减少: 也是逐渐减少或消失，肉眼可观察到


记忆方法: 1）首字母DLDRAD中ADD是增加，RLD想成当然了<==减少

         2）减少的意思是变少mean to grow or make less.