1.affect用作动词，意思是“(在某方面) 引起变化”，“影响”(几乎affect=have an effect on)；affect和influence在表示对人活事的影响时意义非常接近，故有时候是可以互换的；但是affect通常指有形的力量造成的物质或生理上的影响，特别指在坏的方面产生影响。
The cold weather affected everybody's work.
寒冷的天气影响了每个人的工作。
Smoking can affect your health.
吸烟会影响你的健康。
His work has affected his health.
工作影响了他的健康。
affect还可表示引起烦恼、生气、爱等感情或疾病袭扰、感染。
She was deeply affected by the news of his death.
他的死讯使她深受影响。
Will the changes in taxation affect you personally?
税法的变动会影响到你个人吗？
In France alone, more than a million people are affected with some forms of mental ailment.
仅在法国，就有100万以上的人患有某种形式的精神病。
The disease only affects cattle.
这种疾病只对牲畜有影响。
2.effect用作名词，意为“效果，作用，影响”，常用于“have an effect on”短语中，意思是“使……发生变化；对……产生影响”。
His meeting with Stravinsky had a great effect on his musical development.
他同史特拉芬斯基的会见对他的音乐发展产生了很大影响。
这里，have an effect on与affect同义。
His visit had a great effect on them.
他的来访对他们产生了巨大影响。
Unemployment is having a corrosive effect on our economy.
失业对我国的经济起着破坏作用。
Stress has an immeasurably more serious effect on our lives than we realize.
压力对我们的生活造成的影响比我们意识到的要严重得多。
All this had an extremely negative effect on the criminal justice system.
这一切对刑事司法制度产生了极坏的影响。
Watching television had a numbing effect on his mind.
看电视使他头脑麻木。
Oil spills are having a devastating effect on coral reefs in the ocean.
海上溢油对海洋里的珊瑚礁有着毁灭性影响。
The announcement had a dramatic effect on house prices.
这项公告对房屋价格产生了巨大的影响。
His resignation will have a ripple effect on the whole department.
他的辞职将会在整个部门中引起连锁反应。
The increase in the price of oil had a knock-on effect on the cost of many other goods.
石油价格上涨对其他许多商品的价格引起了连锁反应。
This has not had an appreciable effect on production.
此事未对生产造成显著影响。
All this publicity has had a snowball effect on the sales of their latest album.
所有这些宣传对他们最新唱片的销售产生了一种滚雪球效应。
My father's death had a profound effect on us all.
父亲的去世深深地影响了我们全家。
The road safety programme is having a demonstrable effect on road users
道路安全方案在道路使用者身上逐渐显现出明显的效果。
The crisis had a negative effect on trade.
这次危机对贸易产生了很坏的影响。
Does television have an effect on children's behaviour?
电视对孩子的行为有影响吗？
The news had a destabilizing effect on the stock market.
这消息引起了股市的动荡。
Lack of money will have an adverse effect on our research programme.
缺少资金将对我们的研究方案有不利影响。
Modern farming methods can have an adverse effect on the environment.
现代农业耕作方法可能对环境造成负面影响。
Cities have a powerful magnetizing effect on young people.
城市对青年人有着强大的吸引力。
The price increase has had no perceptible effect on sales.
这次提价没有对销售产生明显的影响。
Overseas investment has had a positive effect on exports.
海外投资对出口有积极影响。
The parting from his sister had a positive effect on John
和姐姐分开对约翰来说有好处。
Using computers has a beneficial effect on children's learning.
使用计算机对孩子们的学习有益。
I believe he would have had a stabilising effect on the team.
我相信他原本可以让全组人稳定下来的。
effect还用于be in effect(有效，生效)，come/go into effect(生效), take effect(生效)，bring/carry/put into effect(使生效，实现) 等短语。
The coach says that players must be in bed by midnight; and that rule is in effect tonight. 教练说，运动员必须在午夜前就寝，这一规定今晚生效。
A new system of taxation will come/go/be put/be brought/be carried into effect next May. 新税制将于明年5月生效。
effect作动词用，意为“产生，引起(bring about)；实现，完成(accomplish)”。
We are determined to effect our plan/purpose by any means available.
我们决心采取一切可能的方法实现我们的计划/目的。
He assured them that he would not have the slightest difficulty in effecting a quick sale. 他向他们保证，在实现促销方面他不会有丝毫困难。
3.influence意为“影响”，可指好的影响，也可指坏的影响，较affect语气强。通常指无形力量所造成的“潜移默化的”或“持久或重要的”影响，尤指感情或态度上的影响。
She is easily influenced by her friends.
她很容易受朋友的影响。
His writings have influenced the lives of millions.
他的作品影响了千百万人。
What influenced him to take up teaching?
是什么影响他去从事教学工作？
My teacher influenced me to study physics in the university.
在大学里我的老师影响我去研究物理。
We became the best of friends and he influenced me deeply.
我们成了最好的朋友,他深深地影响了我。
One's health influences one's behavior.
一个人的健康影响一个人的行为。
Don't let me influence your decision. 不要让我影响了你的决定。
These principles powerfully influenced the course of the revolution.
这些原则有力地影响了革命的进程。
A number of social factors influence life expectancy.
诸多社会因素左右着人的预期寿命。
He is trying to improperly influence a witness.
他在试图误导证人。
influence有时接“宾语+不定式”复合结构，意为“促使，劝说”。
Great importance is attached in that factory to influencing workers to produce more goods by praising them and bettering their working conditions.
那个工厂非常重视通过表扬和改善工作条件来促使工人生产更多产品。
Her husband influenced her to accept the job.
她丈夫劝说她接受这项工作。
也可作名词：
Violent programmes on television may have a bad influence on children.
电视暴力节目很可能对孩子们产生极坏的影响。
Van Gogh had a major influence on the development of modern painting.
凡·高对现代绘画的发展有着重大影响。
Television has a strong influence on people.
电视对人有很大的影响。
Teenage idols have a strong influence on our children
青少年偶像对孩子们的影响非常深。
Several teachers at school in Liverpool had a special influence on me.
利物浦的几位学校老师对我有特殊的影响。
Do you believe that we can have an important influence on anyone we meet?
你相信我们能对我们遇到的任何人产生重要影响吗?
They have had a growing influence on the district.
他们在这个学区的影响力越来越大。
It had a bad influence on schools and the society.
它对学校和社会产生了不良影响。
My mother, whose guiding principle in life was doing right, had a far greater influence on me.
我母亲的生活原则是做事堂堂正正，她对我有着更为深刻的影响。
No job has more influence on the future of the world
没有哪份工作能对世界的未来有更大的影响。
The girls in a class tend to have a civilizing influence on the boys.
班上的女生往往能让男生文雅起来。
She had a disruptive influence on the rest of the class.
她搅扰了班上其他的学生。
His paintings had a strong influence on me as a student.
我当学生时，他的画对我产生过强烈的影响。
The media has a powerful influence on public opinion.
传媒对于舆论有很大的影响。
His family have been a very positive influence on him.
他的家庭对他有十分良好的影响。
I thought Sue would be a good influence on you
我认为苏能对你产生良好影响。