词根：umbr = shade, to shadow（阴影）
来源于拉丁语 umbra 阴影 意为shade,to shadow，omber为 umbr 的变体。
同源词：
1. adumbrate（使看起来非常模糊 ad(=to,intensive) + umbr(=shadow)）
vt.勾画轮廓；预示
adumbration n.轮廓；预示
adumbrative adj.暗示的；预示的，笼统预示的；轻描淡写的
The reduced quarterly earnings adumbrate layoffs down the road. 季度收益削减预示着将要裁员。
2. umbrage （-age (n.) 名词后缀， 树下的阴影部分，即树荫 / 荫影）
n.不快，恼火；
umbrageous adj.多荫的；成荫的；易怒的
give /take umbrage at 因...使感到不愉快
3. umbrella （-ella (n.) 表示小，遮掩太阳，使之留下阴影供人遮凉的小工具，即伞）
n.雨伞；<喻>（政治、经济界等的）保护伞
under the Conservative umbrella 在保守党的保护下
umbrella stand 伞架
4. inumbrate （in- 加强意义、-ate (v.) 动词后缀，把阴影投入某物的内部，即投以暗影 / 荫蔽）
v. 投以暗影 ; 遮暗 ; 荫蔽
5. penumbra （pen- 半、-a (n.) 名词后缀，某物阴影的一半，即半影）
n. 半影
6. umbra
n.（太阳黑点的）中央黑暗部分；本影（日蚀时地球和月球的影子）
7. umbral
adj.阴影的；成荫的
8. somber
adj.微暗的；暗色的；阴沉的（在阴影下）《so- = sub- (under) + (o)mber = umbr(shadow)》
词根：lec ( let , lic, lig) = to entice
来自拉丁语的lec意为to entice,它的变形为let,lic,lig等。
同源词：
1. delectable（引诱、唆使分离出来的 de (=away,from) + lec(=entice)）
adj.令人愉快的，使人高兴的，宜人的；好吃的
delectation n.愉快
The smoked salmon was absolutely delectable. 熏鲑鱼真是美味可口。
2. dilettante
n.（艺术等的）一知半解者，业余艺术爱好者 *di<dis(=away,from) ,let,lec(=entice)
3. delicate
adj.微妙的，需要小心处理的；柔软的；纤弱的；精致的，精巧的；易损坏的；（光线）柔和的；（感觉）敏锐的，敏感的；（仪器）精密的；（食物）清淡的；鲜美的 *di<dis(=away,from) ,let,lec(=entice)
delicate situation/question 微妙的事态/棘手的问题
delicate skin of a young girl 小女孩柔嫩的肌肤
delicate workmanship 精巧的工艺
delicate china 易碎的瓷器
delicate child 娇弱的孩子
delicate shade of pink 浅粉色
delicate sense of smell/touch 敏感的嗅觉/触觉
delicate instruments needed by scientists 科学家们所需的精密仪器
delicate food 美味的食物
4. delicacy
n.精致，精美；优雅；敏感；微妙；棘手；柔软；（身体）纤弱；美味，佳肴
the delicacy of her features 她容貌的优雅
The political situation is one of great delicacy. 政局是最微妙的情形的之一。
of extreme delicacy 非常棘手的
all the delicacies of the season 该季节的所有美味
table delicacies 各种美味、精美的食物
5. delicatessen
n.（出售自己做好的肉、沙拉、熏鱼、香肠、罐头等的）熟食店（在美国多被称做deli)
6. delicious
adj.美味的，香喷喷的；妙的，有趣的
delicious cake 美味的蛋糕
Sounds delicious 听起来不错
delicious moment 愉快的瞬间
What a delicious joke! 多么有趣的笑话！
7. delight
n.快乐，高兴；乐事，乐趣 v.使人高兴
8. delighted
adj. 高兴的
I'm delighted to see you. 很高兴见到您。
9. delightful
adj. 快乐的；高兴的
delightful holiday 愉快的假期
词根：grat (grac) = thankful, pleasing（喜好）
词根grat来自拉丁语的grat意为thankful,pleasing 等。grac是它的变形。
（*拉丁文gratus(=pleasing),gratia(=favour)——英文字根字典）
同源词：
1. gratuitous adj.免费的，无报酬的；没有理由的（作为感谢而做的grat(=thank,pleasing)）
gratuity n. 遗散费；（军人的）退役金
Your gratuitous cruelty is abominable.I've had enough!你那无端的残忍在令人生厌，我已经受够了！
2. ingratiate vt.(~oneself)使满意，讨好，迎合 （使对方感到好感in(=in) + grat (=thank,pleasing,favor)）
Despite my lack of credentials,I ingratiated myself with the hiring manager.虽然我不够资格，但我逢迎了招聘主管，使其对我满意。
3. congratulate v.祝贺 *con<com(=together)
congratulatory adj.祝贺的 congratulatory letter/telegram 贺信/贺电
4. congratulation n.祝贺；庆贺；(pl.)祝词 *con<com (=together)
Congratulations !祝贺；offer one's congratulations to 对...说祝贺的话
5. ungrateful adj.忘恩负义的，不知感谢的 *un (=not)
6. grateful adj.感谢的，感激的；令人高兴的，令人愉快的
I am grateful to you for your kindness.谢谢你的好意。
grateful letter 感谢信；trees that afford a grateful shade 有宜人荫凉的大树
7. gratis adv./adj.免费地（的）
be admitted gratis 免费入场
8. gratitude n.感谢，谢意
in token of my gratitude 为表达我们的一片谢意
9. grace n.优雅；好意，恩惠；（饭前、饭后的）谢恩祈祷；（神的）恩宠；慈悲；阁下，阁下夫人；（票据等的）宽限期
v.使优雅；使增光
graceful adj.优雅的 graceful dancer 优雅的舞蹈家；graceless难看的；粗俗的，不知礼的；graceless behavior 粗俗的行为；gracious 亲切的；慈悲的；her gracious Majesty the Queen 女王陛下
10. disgrace n.丢脸，耻辱；失宠
v.使丢脸，玷污；使失宠 *dis(=not)
disgraceful 可耻的；disgraceful behavior可耻的行为
11. ingrate n.忘恩负义的人 (in- = not)
ingratitude n.忘恩负义
12. ingratiate v.讨好；逢迎（使高兴向着某人）《in- = toward》
ingratiation n.讨好；巴结
词根词缀：gehenna-
【来源及含义】Hebrew > Greek > Latin: hell or hellfire
【相关描述】Moloch [MOH luhk] or Molech (Hebrew, melech: king). He was the god of the Ammonites, to whom children were made "to pass through the fire" as sacrifices. Children were dedicated ("passed over") and burned to Molech at the Tophet in the Valley of Hinnom near Jerusalem.
During the monarchical period of the Hebrews, the site was an infamous high place (called "topheth" and derived from an Aramaic word meaning "fireplace"), where some of the kings of Judah engaged in forbidden religious practices, including human sacrifice by fire; as mentioned earlier.
Probably because of these associations with fiery destruction and judgment, the word "Gehenna" came to be used metaphorically as a designation for hell or eternal damnation. As such, Gehenna is to be distinguished from Hades, which is either the bode of all the dead in general or the place where the wicked await the final judgment. In the New Testament, Gehenna designates the place or state of the final punishment of the wicked. It is variously described as a fiery furnace, an unquenchable fire, or an eternal fire prepared for the devil and his angels.
【相关词根词缀】 Cross references of word groups that are related, directly, indirectly, or partly to: "fire, burn, glow, or ashes": ars-, ard-; -bust; cand-, cend-; caust-, caut-; crema-; ciner-; ether-; flagr-; flam-; focus, foci-; fulg-; ign-; phleg-; phlog-; pyreto-, -pyrexia; pyr-; spod- (ashes; waste); volcan-.
【同源单词】gehenna, gehenne, gehennical
词根词缀：lygo-, lyg-
【来源及含义】Greek: shadow, shadowy; shade, darkness; twilight; gloomy
【相关词根词缀】Other related "dark; shadow, shade; black" units: melan-; nigri-; nocti-; nycti-; scoto-; skio-; umbra-.
【同源单词】lygomania, lygophil, lygophile, lygophobia
词根词缀：melano-, melan-, mela-, melen-
【来源及含义】Greek: the color black; dark
【相关词根词缀】Other related "dark; shadow, shade; black" units: lygo-; nigri-; nocti-; nycti-; scoto-; skio-; umbra-.
【同源单词】hepatomelanosis, leucomelanous, melancholia, melancholiac, melancholic, melancholy
词根词缀：niger-, nigri-, negr-
【来源及含义】Latin: the color black
【相关描述】The word "negro" comes from Latin neger through French négre and Spanish and Portuguese negro.
【相关词根词缀】Other related "dark; shadow, shade; black" units: lygo-; melan-; nocti-; nycti-; scoto-; skio-; umbra-.
【同源单词】denigrate, denigrated, denigration, denigrative, denigrator, dignigratory
词根词缀：nocti-, noct-, nox
【来源及含义】Latin: night
【相关词根词缀】Other related "dark; shadow, shade; black" units: lygo-; melan-; nigri-; nycti-; scoto-; skio-; umbra-. Another related "night" unit: nycti-.
【同源单词】equinoctial, equinoctium, equinox, noctalbuminuria, noctambulate, noctambulation
词根词缀：nubi-, nub-
【来源及含义】Latin: cloud, fog; shade; dark or obscure, not easy to comprehend
【同源单词】Caput inter nubila condit, nuance, nubecula, nubia, nubiferous, nubiform
词根词缀：nycti-, nyct-, nycto-, nyc-
【来源及含义】Greek: night; a relationship to darkness, dark
【相关词根词缀】Other related "dark; shadow, shade; black" units: lygo-; melan-; nigri-; nocti-; scoto-; skio-; umbra-. Another related "night" unit: nocti-.
【同源单词】epinyctal, epinyctis, geonyctitropism, nychthemeron, nyctalopia, nyctamblyopia