1.deplete v.倒空，耗尽(to drain．to exhaust)
例:A se ries of costly wars haddepleted the nationaltreasury.
2.depletion n.消耗，损耗(the act of decreasingsth．markedIy)
例:Unlike cod and haddock, there are no legal sizelimits on catching monkfish, which contributes to its depletion by being overfished.
3.deposit v.储蓄(to put in a bank);放置( to place)；n.存款(money deposited in a bank)；押金(money given as a pledge or down payment)；沉积物 (something laid down)
例:Most of the gold deposits discovered during the original gold rushes were exposed at theEarths surface.//Ms. Fox deposited $10,000 in a new account at the annual interest rate of 12 percent.
4.deprecate v.反对( to disapprove)；藐视(to belittle)
词根记忆：de(去除)+prec( =preci价值)+ate -去掉价值--藐视
例:They deprecate the numerous Native American cultures.
5.depreciation n.贬值（falling in value）
例:Because of rapid technological change,computers have a fast depreciation.
6.depress v.使沮丧(to sadden)；削弱(to lessen the activity or strength)；使萧条(todecrease the market value or marketability)
例:Adenosine(腺苷)normally depresses neuron firing in many areas of the brain.//Putting suchlarge amounts of stock on the market would only depress its value.
例:Only one percent of Americans born before 1905 suffer major depression by the age ofseventy-five.//the Great Depression大萧条
8.deprivation n．剥夺(the act or an instance of depriving);缺乏(the state of beingdeprived)
例:Sleep-deprivation is not used to treat depression.//oxygen deprivation缺氧
9.deregulation n.违反规定，撤销管制规定(the act or process of removing restrictions andregulations)
例:Since the deregulation of airlines, delays at the nations increasingly busy airports haveincreased by 25 percent.
10.derivative a．派生的(derived)；无创意的(not original);n.转成物
例:The Madagascar periwinkle has a derivative which has proved useful in decreasingmortality among young leukemia patients.