1.debris n.碎片，残骸(the remains of something broken down)

词根记忆：法语词，注意该词的发音比较特别，末尾的“s”不发音

例:The excavation revealed a pattern of debris and collapsed buildings.

2.debunk v.揭穿真相;暴露(to expose the falseness of)

例:The new data debunked the theory.

3.decade n.十年，十年期(a period of 10 years)

词根记忆：deca(十)+de--十年，十年期

例:Over the past decade the technology of microelectronics has evolved rapidly.

4.decay v./n.腐朽(to rot)；衰退(to decline from a prosperous condition)

例:Wood decays rapidly in the humid climate.//radioactive decay放射性衰变

5.decimal n.小数（fraction expressed in tenths, hundredths, etc.）;a.小数的,十进制的(based on or reckoned in tens or tenths)

词根记忆：decim(十分之一)+al--将数分成十分之一--小数

例:Any decimal that has only a finite number of nonzero digits is a terminating decimal.

6.decimate v.使（数量）急剧减少(to reduce drastically especially in number)

例:Cholera(霍乱)decimated the population.

7.decipher v.破译(to decode)

词根记忆：de(去掉)+cipher(密码)--破译

例:The environmental signal can be deciphered by modern physical or chemical means.

decipherable(a．可破译的)；decipherment(n.破译;译文)

8.declension n.衰退(deterioration)

词根记忆：de+clen(倾斜)+sion--向下倾斜--衰退

例:After gradual dedension down to about 39 hours in 1970, the workweek in the United States has steadily increased.

9.decorate v.装饰，点缀(to adorn)

词根记忆：decor(装饰)+ate--装饰，点缀

例:Male bowerbirds(澳洲产的一种鸟)construct elaborately decorated nests.

派生词:decoration（n.装饰，奖章）;decorative(a.装饰性的)；decorator(n.装饰者)

10.decoration n．装饰，装潢(the act or process of decorating)；装饰品(sth. that adorns, enriches, or beautifies)；奖章(a badge of honor)

词根记忆：来自decorate(v.装饰)

例:Much of the local artisans' creative energy was expended on the creation of Buddha images and on construction and decoration of the temples.