n. 不透明性，费解，难懂，模糊；

[例句] Opacity of the eye lens can be induced by deficiency of certain vitamins...

[例句] He insisted that the mineral content of the water determined the opacity.

n. 选择(option的名词复数 )，选项，选择权，选择能力，[经济]买卖的特权；

[例句] He's argued from the start that America and its allies are putting too much emphasis on the military option...

[例句] What other options do you have?

n. 呐喊，喧闹，大吹大擂，假大空的宣传；vt. （为…）大吹大擂；

[例句] They announced, amid much ballyhoo, that they had made a breakthrough.

[例句] The power of red wine to counteract high cholesterol has been ballyhooed in the press.

int. 哈喽，喂，你好，您好，表示问候，打招

[例句] Hello, Trish...

[例句] Do you want to pop your head in and say hallo to my girlfriend?

n. 开始，开端；

[例句] Decide at the outset what kind of learning programme you want to follow...

[例句] From the outset he had put his trust in me, the son of his old friend.

adj. 乐于助人的，有礼貌的；v. 迫使做( oblige的现在分词)，施惠；

[例句] He is an extremely pleasant and obliging man.

adj. 忘却的，健忘的，不注意的，不知道的；

[例句] She lay motionless where she was, oblivious to pain...

[例句] Llewelyn appeared oblivious of his surroundings.

vt. 过度成长，因年龄增加而失去，年长而不再需要，生物长出；

[例句] She outgrew her clothes so rapidly that Patsy was always having to buy new ones.

[例句] ...outgrown baby clothes.

n. 寡头统治的政府，寡头政治的执政集团，寡头统治的国家；

[例句] Athens was suffering under the rule of an oligarchy that had no concern for the people's welfare.

[例句] ...a protest against imperialism and oligarchy in the region.

adv. 令人不愉快地，讨厌地，冒犯地；

[例句] Some friends of his found the play horribly offensive.

[例句] ...offensive remarks which called into question the integrity of my firm.

n. 精力充沛的人，[物]发电机；

[例句] Myles is a human dynamo.

n. 牛，公牛，牛属动物；

n. 着魔，萦绕，使人痴迷的人（或物），摆脱不了的思想[情感等]，妄想；

[例句] She would try to forget her obsession with Christopher...

[例句] 95% of patients know their obsessions are irrational.

n. 前兆，征兆，预兆，兆头；vt. 预示，预告，有…的前兆；

[例句] Her appearance at this moment is an omen of disaster...

[例句] Could this at last be a good omen for peace?

n. 自然结果，副产物，生长物；

[例句] Her first book is an outgrowth of an art project she began in 1988.

vt. 避免，消除（贫困、不方便等）；

[例句] The use of a solicitor trained as a mediator would obviate the need for independent legal advice...

[例句] This deferral would obviate pressure on the rouble exchange rate.

n. （蒸汽，怒气等的）爆发，破裂；

[例句] ...an outburst of anger.

[例句] ...a spontaneous outburst of cheers and applause...

adj. 沉重的，压迫的，压抑的，沉闷；

[例句] The new laws will be just as oppressive as those they replace.

[例句] ...refugees from the oppressive regime.

n. 汽车，自动；

[例句] ...the auto industry.

n. 动物园，（铁路货车的最后一节）守车，核粒子园；

[例句] He took his son Christopher to the zoo.

[例句] ...the penguin pool at London Zoo.