雅思大作文中有一类题目是因果关系类，具体包括三小类：cause and effect、cause and solution、problem and solution。这三小类问题也可以穿起来，即针对某个topic的cause—effect(即problem)– solution。无论哪种题目，写明因果关系很重要。关于因果关系的表达同学们都很熟悉，无非是BS(because / so)，而且大家也一定很清楚的知道BS在英语中，用了前者就不能用后者的道理。例如：
Because further education has become more accessible for a wider range of people, an increasing number of people have degrees
Further education has become more accessible for a wider range of people, so an increasing number of people have degrees.
1. because of : because后接的是一个句子(主谓宾);because of 后一般直接跟名词。例如：
Because of the increasing number of machine—and as we noted before, machines magnify human effort—then anyone using a machine can
get a higher wage than anyone not using a machine.
2. as / since (除了“因为“外，还有”自从”的意思，使用时要注意避免歧义)
Hours spent on commuting, traffic jams, and fights for parking should diminish, since workers make fewer journeys or work staggered hours
Unfortunately, as the number of people living in the city increases, so do the different problems associated with population growth. (注意此句中的so不表示“所以”，而是“…也…”的意思)
3. thanks to (positive situations 通常适用于结果好的时候)
Thanks to new technology, it's easier than ever to work remotely.
due to (negative situations通常使用与结果不好的.时候)
owing to / attributable to /on account of
Due to /… / On account of extreme weather conditions, damage to property occurs.
4. 当原因需要的表达较多时，我们还可以把以上表达改写为原因状语从句，使用thanks to the fact that /due to the fact that /owing to the fact that 或者on the grounds that ,,,
Will we live longer merely due to the fact that / on the grounds that technology, if implemented properly, will take stress away from our lives
5. caused by / result from 也表原因
Many car accidents were resulted from / caused by a lack of guardrails
1. thus/ therefore / thereby / hence
thus: 表示‘in this/that way’
As a country develops, its cities become the engines of development, thus jobs are available in these areas.
therefore: 表示 ‘for this reason’ /‘because of this or that’
Therefore, the influence of the peer group is important both for one’s own competence and for the relative evaluation of the process itself, given that one sees oneself in relation to others.
thereby: by that means, as a result of that
In some countries, reduced budgets have led to the elimination of busing systems, thereby increasing the use of cars and the congestion they create.
hence: 表示 ‘from this/that’
Drinking lots of water is healthy and reducing plastic waste is great for the environment. Hence, trendy reusable water bottles that you can refill yourself are health-promoting, eco-friendly, and green.
2. As a result / As a consequence
As a result, those people who were indoors had much lighter skin, which means that whiter skin is now associated with having a higher status than dark skin.
As a consequence, environmental health must address the societal and environmental factors that increase the likelihood of exposure and disease.
3. consequently /accordingly
Consequently 更偏重因果逻辑;accordingly 更偏重后续解决
Water pollution affects drinking water, rivers, lakes and oceans all over the world. This consequently harms human health and the natural environment.
Some of the laws were contradictory. Accordingly, measures were taken to clarify them.
1. cause (v.) 引起
The amount of garbage produced by the people also increases which causes sanitary landfills to fill up faster.
2. lead to/ result in 导致
注意这里是result in, 后跟结果，前面提到的result from后面跟的是原因。
The society’s attitude to food often leads to over-consumption.
3. bring about: to cause to take place 引起，带来(注意使用时更倾向于“带来“这个意思)
The internet technologies that have brought about so much social change were scarcely imaginable just decades before they appeared.
4.spark off 引发、引爆 ，具体指引发比较严重的后果、冲突等(=trigger / activate)，或指”点燃“(=inspire)
Spark off a series of problems / a chain of events related to…
They can spark off each other's talents
More likely than not, getting a vehicle from point "A" to point "B" involves combustion of a fossil fuel, a process that emits gasses and affects the environment and the ozone layer.
People's behavior is influenced by circumstances and events, friends and family, education, job prospects, income, housing and environment.
2.impact on 对…产生影响(impact 一般做名词使用，也可以作为动词
Over the last few decades, there has been a tremendous growth in information technology, which can impact on our everyday life.
3. give rise to 使发生
The decrease inthe number of bicycles and cars might give rise to another new set of problems.
1. cause (of sth.)/ reason 原因
Obesity can be divided into three main causes – diet, lifestyle and education.
Thousands of people migrate to the cities not only for jobs but also for educational and personal reasons.
2. result (for sth.)/ effect 结果
This is a difficult problem with many serious effects on the individual and country.
Another result is lack of self-esteem.
3. causality 因果关系(cause and effect) causation 原因
The correlation between population and housing price does not indicated causality, only the association. 这里的causality也可以换成：causal effect (因果效应)
Such a causality-driven, prevention-focused approach to homicide and other serious crime would revolutionize our conception of criminal justice, moving from the imposition of “just deserts” to the enlightened pursuit of a less violent society.
4. impact/influence 影响
This area is often overlooked but has a tremendous impact on your life
Friends have a big influence on the way that we use social media—from unwritten rules to buying decisions and so much more.
形容词系列(因果)表示因果的形容词不是很常用，使用时多和factor, element 结合
1. causal 原因的，因果的
Low income and elderly are among the potential causal factors of prevalence of obesity among adults
Measures other than ratings will prove more consequential
Family is the most influential factor on happiness.