1.deplete v.倒空，耗尽(to drain．to exhaust)

词根记忆：de（去除）+plete（满）一使不满一倒空

例:A se ries of costly wars haddepleted the national treasury.

派生词：depletion（n.损耗）

2.depletion n.消耗，损耗(the act of decreasing sth．markedIy)

来自depIete（v.耗尽，倒空）

例:Unlike cod and haddock, there are no legal size limits on catching monkfish, which contributes to its depletion by being overfished.

同根词：complete(v.完成;a.完整的)

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)

词根记忆：de（起强调作用）+posit(放)一把财物妥善保管一储蓄

例:Most of the gold deposits discovered during the original gold rushes were exposed at the Earth's surface.//Ms. Fox deposited $10,000 in a new account at the annual interest rate of 12 percent.

派生词：depositor(n．存款人)：depository(n.存放处)

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）

词根记忆：来自depreciate(v.贬值)

例:Because of rapid technological change,computers have a fast depreciation.

同根词：appreciate(v.赏识)

6.depress v.使沮丧(to sadden)；削弱(to lessen the activity or strength)；使萧条(to decrease the market value or marketability)

词根记忆：de（往下）+press(压)--往下压一削弱

例:Adenosine(腺苷)normally depresses neuron firing in many areas of the brain.//Putting such large amounts of stock on the market would only depress its value.

派生词：depressed(a．沮丧的，消沉的)；depression(n.抑郁;萧条)；depressive（a.令人沮丧的;抑郁的）

7.depression n.消沉(dejection)；萧条（期）

词根记忆：来自depress(v.消沉，沮丧)

例:Only one percent of Americans born before 1905 suffer major depression by the age of seventy-five.//the Great Depression大萧条

派生词：depressive(a．郁闷的)

8.deprivation n．剥夺(the act or an instance of depriving);缺乏(the state of being deprived)

词根记忆：来自deprive(v.剥夺)

例:Sleep-deprivation is not used to treat depression.//oxygen deprivation缺氧

同根词：privacy(n.独处，私下);privation(n.贫乏)

9.deregulation n.违反规定，撤销管制规定(the act or process of removing restrictions and regulations)

词根记忆：来自deregulate（v.解除对…的管制）

例:Since the deregulation of airlines, delays at the nation's increasingly busy airports have increased by 25 percent.

同根词：regulation(n.规则；校准)

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 decreasing mortality among young leukemia patients.

同根词：derivation(n.引出；来历；词源)