高中英语作文my weekend(实用20篇)

When I was a child, I raised a pet, named Lucky.Actually he is a cat.His fur is soft with yellow and white color.Lucky is a good boy.He always behaves well.I remember when my uncle took him back to my home at first, I was afraid of him.But soon I found him is very interesting.I started to play with him.As time goes, we like each other very much.And then my uncle gave him to me.I was so happy.Now he always lies beside me quietly, when I’m doing my homework.As winter comes, he will sleep with me.sometimes he will dance for me, which is very funny and sometimes his hands are wet would leave many “plum flower” on the ground.He is so lovely.

在我还是个孩子的时候，就养了一只叫做幸运的宠物。其实他是一只猫。他的毛很柔软，是黄色和白色。幸运的是一个好男孩。他总是很听话。我记得当我叔叔带他来到我家的时候，我很怕他。但不久后，我发现他很有趣。我开始和他玩。随着时间的推移，我们都互相非常喜欢对方。之后我叔叔就把他送给了我。我是如此的高兴。现在他总是在我做家庭作业的时候悄悄地躺在我的身边。冬天来了，他会跟我一起睡。有时他会为我跳舞，那是非常有趣的，有时他的爪子湿了就会在地面上留下许多“梅花”。他很可爱。

Since I go to middle school, I have to learn many subjects. Though I am not

the best student in class, but I won’t give up. I always tell myself to work

hard, because if I want to compete with other students, I need to make great

effort. People are easy to deny themselves when they face difficulty. If they

fail one time, then they will doubt the effort they have made. Actually, we are

not studying in vain. What we learn will be a great help to improve ourselves.

The thing we learn decides what kinds of person we are. So don’t deny yourself,

as you will see the value you have stored before in the future.

Last year, I went to Guilin for travel. On the train, I felt so bored. A

girl who sat next to me was reading a book, which caught my attention. I asked

her about the book, I found that I had read it before and then we discussed

about the novel. We talked happily, when the train arrived, we got off together.

When we got aparted, we promised to keep in touch. We communicated by the

computer. Now a year has passed, we become good friends and I miss her all the

time. She is a genuine friend. I plan to go to Guilin again and then we will

meet.

every one has a dream. i have a dream, too. i have a dream that one day i could become a math teacher.

i love math very much, because i think math is quite useful. its useful when people are buying things. its useful when students are learning subjects like physics and chemitry. and its useful when scientists are doing experiments. teachers can not only help students to learn things but also teach the students to apply what they learn into practice.

therefore, i hope to be a math teacher in the future. i want to help more students learn math.

Yesterday,I went to have a picnic with my old classmates.We dated with each other several days ago.And we were all expecting the days come. At last, the excited day came. We went to the part where we have decided to have the picnic. During the picnic ,we talked with each other,played games,and so on. On balance, I had a nice day and I will never forget it.Because it is so happy in the picnic and we remaided so many pleasures things in our childhood.

2we had a picnic in fall last year. first we climbed to the top of the hill. we saw many pupils there. we talked ,laughed and played together. then at picnic time, we shared our food .we saw a beautiful stream near by. but there was much rubbish in it. thats a pity .we thought we should tell the people to protect our living environment. so after our picnic, we put up several signs near the stream. we wrote "please keep the stream clean and beautiful" on the signs. time to go home, we said goodbye each other and we made an appointment of next year.. on our way home, we all thought thats a very interesting picnic.

大概翻译：

昨天，我到有我的老彼此几天给classmates.We野餐ago.And大家都期待的一天来。最后，兴奋那天。我们去的地方，我们决定有野餐的一部分。在野餐，我们彼此交谈，玩游戏等。总的来说，我有一个愉快的一天，我永远不会忘记it.Because是这样的野餐高兴，我们remaided这么多的乐趣在我们的童年的事情。

2we曾在去年秋季野餐。首先，我们爬上了山顶。我们看到有许多学生。我们交谈，笑着一起玩。然后在野餐时，我们分享我们的食物。我们看到了一个美丽的流附近。但有许多内容是垃圾。这是一个遗憾。我们认为我们应该告诉人们保护我们的居住环境。所以我们的野餐后，我们提出了几个附近的流标志。我们说“请保持清洁，美丽的流”的标志。回家的时候，我们彼此说了声再见，我们进行了一个任命明年..在回家的路上，我们都以为这是一个非常有趣的野餐。

With the development ofscience and technology ,different kinds of pollution has been produced andcaused global concern recently.

As we know, people have beenliving on the earth for thousands of years, human activity damaged natural environment, such as excessive abuse of natural resources ,the sewage dischargedfrom factories ,the animal slaughter ,kinds of chemical fertilizers andgreen-house effect. All that is mentioned above has a bad impact on the eco-system .Now, many animals aredying out. We are suffering from unhealthy food and water, we are faced withharmful rays and global warming. It was ourselves who had made a series oftroubles. As you can see, we are the final victim.

Above all, if we human beings cannot recognize theseserious problems and try our best to solve them soon, we would finally lose theenvironment suitable for us to live. So, it is our duty to protect theenvironment ,but what should we do to protect it?

In my opinion, the first and important thing is tounite all forces ,that is to say---gather all hearts together. Next we shouldprotect and plant more trees, which can dispose of the dust in the air. As forfamilies, it is effective to ride bicycles rather than drive cars. Don’t litteranywhere as you like. In addition, sorting and recycling the rubbish also playan essential role in the protection of our earth. We’d better call on everyone aroundus to lead a low-carbon life, as it may make a difference to the environment.

Thus, it’s high time that we did something to improveour surroundings. Everybody should raise the awareness to protect our motherearth. Let’s appeal to more people to join us.

All in all ,there’s no doubt that keeping the balanceof human and nature ,we will benefit a lot.

我们的春节是中国人一年中的第一个传统佳节，它标志旧的一年结束，新的一年已经开始。年夜饭，是春节的重要活动之一，中国的百姓家庭对年夜饭极为重视。正月初二，我和爸爸妈妈一起到奶奶家吃年夜饭。

在今天来的人特别多，奶奶家显得格外热闹，年味超浓。姑姑、叔叔和我爸爸正聊得热火重天。他们边嗑瓜子，边滔滔不绝的聊着各种话题。表哥和嫂子在房间里逗小baby开心，看着小宝贝的笑脸，他们别提有多开心了。而我和俩位表姐则更是“肆无忌惮”了。我们三人盘腿坐在沙发上，悠闲自得地玩着ipad上的割绳子，时不时传出一阵阵爽朗的笑声。

又过了一会儿，奶奶慈祥地把我们带进房间，塞给我们每人一个印着“马”的红包，我们接过红包，笑盈盈的谢谢奶奶。

很快的还有5分钟就到6点了。姑父把我们安排到圆桌上的各个座位上，我和2位表姐左右邻座。先上一道饭前甜点“蔬菜沙拉”开开胃。我们三个吃货纷纷拿勺子一勺勺地舀着沙拉，没一会儿，沙拉就差不多吃完了。姑姑笑着说：“慢点吃，每人和你们抢。”这时，第二道菜“年年有鱼”上来了。色香味俱全，酱油的味道恰到好处，加上葱花点缀，这道菜别提有多美了。鱼上完了，紧接着就是“清煮虾仁”了。这道菜清甜可口，配上一碗香醋，让人垂涎欲滴。稍后又上了不少好菜，个顶个都是美食，今天来真是有口福了。

晚上，吃完晚饭。大家陆陆续续都散了，我和爸爸妈妈也只好依依不舍的和奶奶说“再见”了，今天一天玩得别提有多开心了，和家人团聚是一件幸福的事。

Music is the important part of my life. The world needs music to amuse

peoples life. As they live in the fast pace, music can bring them the great joy

and relax. Since I was very small, I fell in love with music and every time when

I heard music, my body would move and feel relaxed. The function of music is

various.

There is a famous song, which called let the music heal your soul. A lot of

young people have their favorite singers. When they see their idols face to

face, they would say thank you to the singers, because their songs inspire these

young people to move on in the dark days. The songs deliver positive messages to

the public and inspire them to never give up.

Listening to the music is the main way for the young people to release

their pressure. Every day before I sleep, I will listen to the light music,

which helps me to take relax and make me sleep well. The reason why so many

people like to KTV after their work lies in releasing pressure. They need to

shout and then forget about the annoyance.

Music is favored by everyone and it is the indispensable part of our

life.

last year, my friend gave me a little dog. i was fond of him very much. i liked to play with him after school and he liked to follow me wherever i went. i was very glad that i had a "body guard".

last winter i was very busy with my lessons and came home very late every day.however, no matter how late i went home, my dog used to stand at a comer near my school waiting for me. when i passed there, he barked two or three times then ran towards me. it seemed that he was calling me.

my dog not only,took good care of me, but also was respoasible at home. when strangers came to my house, he barked at them but not hurt them. what a lovely dog he is! (135 words)

我家的小狗

去年，朋友送我一只小狗，我非常喜欢它，放学后就和它一起玩耍，无论我走到哪儿它都跟在身后。我很高兴有这样一位“保镖”。

去年冬天我忙于功课，每天回家都很晚。然而无论我到家多晚，这只小狗总是在学校附近的一个角落处等我。当我从那经过时，它全冲我叫两声然后跑过来，似乎它是在叫我。

我家的狗不但对我照顾周到，而且还肩负着看家的重任，每当有陌生人来到我家，它总是叫个不停，但并不咬他们。多么可爱的一只狗啊!

[我的宠物狗高中英语作文

Today, as the economy develops fast, people can buy what they need, the

producers provide them all the new things, so the factory produce many products,

in order to make the biggest profit, they don’t deal with the pollution. Water

gets polluted, it does harm to people’s health, we drink water everyday, the

government controls the producers to figure out some ways to deal with the water

pollution.

一、遣词方面：用词要贴切而丰富，善用短语 ,词汇是语言的建筑材料，文章的好坏，选词很关键，如果用词精湛，就会使文章“亮”起来。

1、措辞要贴切具体

试比较下面句子：

A man is walking down the street.

A man is strolling down the street.

通过比较可以看出，前一句不如后一句表达得具体、生动。一个词如果内涵越具体，那么在特定的场景中恰当地使用它，就会收到意想不到的效果。很多同学写作时常随便用一个很笼统的词来描述一个具体事物或人，如 a nice man给人感觉很笼统空泛，我们可以用很多有个性的、具体的词描绘一个人，如 generous(大方的，慷慨的)，humorous(幽默的)，smart(漂亮的，潇洒的)，kind-hearted，warm-hearted，hospitable(好客的,招待周到的)，gentle(文雅的)，optimistic(乐观的)，easy-going(随和的)，spirited(英勇的)，cultivated(有教养的)，manly(有男子气概的)，knowledgeable(知识渊博的)等等。

2、要善于运用短语

短语用得好，会给评卷员留下深刻印象。如：

When he was a child，he wanted to learn everything.( 普通)

When he was a child，he had a strong appetite(胃口) for knowledge.(高级)

3、要避免汉语思维

用词要符合英语习惯，避免汉语思维的影响，如某些名词和动词搭配已约定俗成，不能随意打乱其搭配习惯，否则会显得生硬和词不达意。如汉语中的“学到知识”，英语中就不能说“learn knowledge”，而要说acquire knowledge (获得知识) 。类似的动宾结构还有achieve success (获得成功)，gain reputation (获得声誉)，attain ones end (达到目的)等。

二、造句方面：句式要准确而多变，活用复合句

简单句用得太多，会造成文章读起来乏味。在评卷员看来，同样意思的内容，能够运用比较复杂的句式结构来表达，当然会认为其运用语言的能力要比只会用简单句来表达要强，评分自然就高。

1、巧用非谓语动词

运用非谓语动词，可使文句看起来更简洁，使语言更加丰富多彩，重点更加突出，增加文采。如：

I covered my ears，trying to keep the noise out，but failed. (2004广东卷)

2、巧用with复合结构

“with+名词/代词+现在分词/过去分词/形容词/副词/介词”结构，常作伴随状语以增加被描绘内容的生动性和情感性，使文章读起来更简洁明了。试比较：

I couldnt go on studying because there was so much noise troubling me. (普通)

I couldnt go on studying with so much noise troubling me. (高级)

3、巧用复合句

高考评分标准强调使用语法结构的数量和复杂性，鼓励考生尽量使用较复杂的结构，并且对由此产生的错误采取了宽容的态度。如果恰当运用各类从句，就会使文章出彩。

如：(定语从句) Whats more，people have easy access to the Internet，which enables them to send and receive e-mails whenever they like.

4、巧用倒装句、感叹句、强调句、虚拟语气句等

使用这些句式可使文章化平淡为生动，加强语气，使评卷老师感受作者的强烈情感。

(倒装句)Only in this way can Internet Bars be well used by people.

(感叹句)I thought，“How hard mum is working! She must be very tired.”

5、巧用排山倒海句

如能运用一个个排比句、对偶句、不定式或短语，可令文章增色不少，会给评卷员眼前一亮的感觉。如：

The purpose of the program are to make our school more beautiful，to make the air cleaner and fresher，and to turn our school into a better place for us to study and live in.

三、谋篇方面：结构要清晰而流畅，巧用过渡词

众所周知，语言的最高层次不是传统语法所说的句子，而是语篇。语篇指的是一系列连接的语段或句子构成的语言整体。一篇好的文章不但句子正确，要点齐全，更重要的是有效地使用了语句间的连接成分。因此，恰当使用好连接性的词语和句子，是使作文获得高分的一个重要因素。

下列各组表示列举或补充的短语或句式非常实用，对高考写作很有帮助：

(1)Firstly...，secondly...，thirdly...，finally...

(2)In the first place...，in the second place...，in the third place...，lastly...

(3)to begin with...，then...，furthermore...，finally...

(4)to start with...，next...，in addition...，finally...

(5)first and foremost...，besides...，last but not least...

(6)most important of all...，moreover...，finally...

如果只有两层意思，可选用下列两组中的任一组：

(1)On the one hand...，on the other hand...

(2)For one thing..., and for another thing...技巧，希望对大家有帮助

As we all know, pollution is harmful to living beings. There are many different types of pollutions in this world. For instance, water pollution, air pollution, noise pollution and so on. Water pollution cause many kinds of disease that have negative effects on human beings, sometimes the diseases will take people’s life away. Dirty air will increase the rate of getting lung cancer. While the noise pollution will cause insomnia. People’s health condition will be damaged.

In my humble opinion, people should take measures to control the pollution. Recently, not only the government, but also individual has taken part in the action of protecting the environment. This is a good sign. Rivers are being cleaned, air is purified, and the people come to realize that the importance of protecting the environment.

However, this is not enough, the problems are still exist. Not all of them have been solved. Some factories are still pouring dirty water into the rivers or give off the toxic gas into the sky. We should know that protecting the environment needs everybody’s effort.

I have a cat named mimi. Its hair is as white as snow. I often play games with it. It amuses me a lot and I treat it as a little friend. Every morning, I would say goodbye to it before I go to school and mimi would wave its front-legs to me. It brings me a lot of pleasure. But it takes time and costs money to keep the cat. My parents and I spend much time taking care of it, feeding it and cleaning it. We have to clean the house from time to time, or the cat will make them dirty and smelly.

我有一只猫，名叫咪。它的毛像雪一样白，我经常和它一起玩。它使我很开心，我也把它当小朋友一样对待。每天早上，我去上学之前都会跟它说再见，它也人向我晃晃前爪。它给我带来了很多快乐。但是，养猫是要花费时间和金钱的。我父母和我花费很多时间照看它，喂它饭，给它洗澡。我们得经常打扫房间，否则，猫就会把屋子弄得又脏又难闻。

Today, the world is globalized and more and more foreigners come to China

to seek for business cooperation. Many years ago, a non-profit organization

named the second Saturday of July as the International Day of Cooperatives. Its

purpose is to call for more cooperations between countries.

With the development of Internet, the world gets smaller, because the

communication between countries has increased. America is the superpower all the

time, but during recent times, there are so many business cooperation between

Chinese people and American people. It is known to all that China’s market is

full of vitality, so there is no doubt that cooperation between countries will

be the main trend.

The cooperation happens all the time and it promotes the working

efficiency. People can share the information and technology. They learn from

each other, so as to gain the precious experience and make progress. China is

the future, so more and more foreigners learn mandarin. They want to find a

place here and make their achievement. We also can gain a lot when we work with

them.

Nowadays, electronic music is very popular around the world. First electronic music got popular from Lady Gaga, her creative dressing styles caught people’s attention and then people started to notice her music. They fell in love with her electronic music. Unlike rock and roll music, electronic music is more favorable by me. It makes me excited and I am totally lost in the wonderful music. Once my friends and I went to a music festival. There were so many people standing there and listening to the music. Especially when the DJ came out and everybody got excited. When the DJ played electronic music, my friends and I shook our bodies and joined the crowd to dance. It was such a wonderful experience for me. I will never forget the power of electronic music. It brings people together and share the same emotion.

电子音乐现在在世界各地都很受欢迎。电子音乐是从Lady Gaga开始流行的，她奇特的穿衣风格引起了人们的注意，然后大家开始注意到了她的音乐，并且爱上了她的电子音乐。它跟摇滚音乐不一样，我更加喜欢电子音乐，这可以让我兴奋。我完全迷失在美妙的音乐中。有一次我和我的朋友们去了一个音乐节。很多人站在那里听音乐。特别是当DJ出来时，每个人都很兴奋。DJ播放电子音乐时，我和我的朋友都扭动着身体，加入了人群中跳起舞来。这对我来说是那么奇妙的经历。我永远不会忘记电子音乐的力量，它使人与人走到一起，分享着相同的情感。

Today is the first day of the New Year, the morning of fresh air and

sunshine, mother took me to feel the New Years day outside the atmosphere.

Street vehicle comings and goings, flowing very lively, mother took me to

the supermarket to buy things, supermarket bustling, originally people rush to

buy New Year gift! My mother said he wanted to buy a toy, I say: "I is the big

kid dont car these toys, it would save some money to buy school things," then I

will take some learning supplies and a cake billet to do our own cake to

celebrate New Years day. On the way back to my grandmas I saw many shops,

supermarkets in glass written on New Years day wishes everybody happy, return

to my grandmas I took the cake billet and brother in above the text is

made.

Less than half an hour a nifty bright homemade cake will appear in the

present, this is really a happy New Year!

Nowadays, pets become so close and friendly to our human-beings that more

and more people enjoy keeping them. Pets can bring them a lot of joys and

happiness, because playing with pets is a good way to communicate with the

nature. Besides, pets can comfort old people who live alone. With the companion

of pets, they won’t feel lonely. Nevertheless, I’m not interested in keeping

pets at all. For one thing, keeping pets is bad for environmental protection,

since pets usually make a lot of noise and contaminate the roads. For another,

the virus carried by pets may cause fatal disease. What’s more, sometimes pets

may attack people when they are unhappy. Consequently, we had better not keep

too many pets, so as to ensure our health and security. Besides, those pet

lovers must take some effective measures to prevent their pets from hurting

people and polluting our environment.

Love in high school is a very sensitive topic, the students in high school have come to the age of being mature, inside, they desire to love someone, but it is the awkward time. First, they need to focus their attention so that they can enter a better college, second, their parents are strongly objective to their love, the teachers even ban the love relationship between students. As a student, they have their own rights to love someone, the inner desire and the objection from parents and schools make them struggle to their emotions. In my opinion, high school students have so many pressure, they should put aside their love emotions for a while, they need to focus on the study, when high school time ends, they can choose their love. It is much easier, if you want to love at the time, then to love. No one will stop you.

爱在高中来说是一个很敏感的话题，高中生已经来到了即将成熟的年龄，他们渴望去爱人，但是这也是一个尴尬的时间。第一，他们需要集中精力学习，以此来考取一个好的大学，第二，他们的父母强烈反对恋爱，老师甚至禁止学生谈恋爱。作为一名学生，他们有自己的权利去爱人，内心的欲望，父母和学校的反对，让他们在情感上做挣扎。在我看来，高中生有很多压力，他们应该暂时把感情放在一边，需要集中精力学习，当高中时光结束以后，他们可以选择去爱。这容易多了，如果你那时想要去爱，就去爱。没有人会阻止你。

1、 Today and friends of foreign travel, outside air is very good, people feel very comfortable. We all appreciate the fine girls bicycles. We enjoyed the beautiful nature brought. We happily spent a happy day. 今天和朋友一起出外交游，外面的空气很好，人感觉很舒服。我们骑着自行车一路欣赏鸟语花香。享受着大自然带给我们的无限美好。大家开开心心地度过了愉快的一天。

2、 Today Mailehaoduo clothes, and parents take to the streets is happy, the parents have to pay to buy things. Unlike in their street to buy things they like to take a long time but saw the price, Ha-ha, is really very happy. I love my parents, I too thank them for the care and love. `` 今天买了好多衣服，和父母上街就是愉快，买东西有父母帮付钱。不像平时自己上街买东西碰到喜欢的但看了价钱都要考虑好久，呵呵，真的是很开心。我爱我的父母，太感谢他们对我的关心和爱戴了。`

3、 HOW TO GET HAPPINESS 如何获得快乐

there is no doubt that happiness is the most precious thing in the world. Without it, life will be empty and meaningless. If you wish to know how to get happiness, you must pay attention to the following two points.

First, health is the secret of happiness (the key to happiness). Only a strong man can enjoy the pleasure of life.

Secondly, happiness consists in contentment. A man who is dissatisfied with his present condition is always in distress.

无疑的快乐是世界上最宝贵的东西。没有它，人生将是空虚的而且毫无意义的。如果你希望知道如何获得快乐，你须注意下面两点。

健康是快乐的要诀。唯有身体强壮的人才能享受人生的乐趣。

快乐在于知足。一个不满于现状的人终是处在痛苦之中。

4、 BOOKS 书籍

As is well known, books teach us to learn life, truth, science and many other useful things. They increase our knowledge, broaden our minds and strengthen our character. In other words, they are our good teachers and wise friends. This is the reason why our parents always encourage us to read more books.

Reading is a good thing, but we must pay GREat attention to the choice of books. It is true that we can derive benefits from good books. However, bad books will do us more harm than good.

如众所周知，书籍教我们学习人生，真理，科学以及其它许多有用的东西。它们增加我们的知识，扩大我们的心胸并加强我们的品格。换句话说，它们是我们的良师益友。这是为什么我们的父母终是鼓励我们要多读书的理由。

读书是一好事，但我们必须多加注意书的选择。不错，我们能从好书中获得益处。然而，坏书却对我们有害无益。

5、 Fri.,Feb. 5 Rainy

In my dream

Last night ,I dreamed I became a very beautiful brid.I dreamed that I was in a forest. In tht forest,there were a lot of animals.Then,an old bird told us,"we have a very beautiful forest,we should therefore protect it from pollution."All the animals agreed with him.

But the second day,people came into our forest.Many animals were caught.The people wanted to build house and parks in our forest.Many old trees were felled.And then suddenly,nothing was left standing.

I was so shocked and then I bursted out crying.I woke up at midnight.It was only a dream.

二月五日 星期五 雨

在梦中

晚我梦见我变成一只非常漂亮的鸟.我梦见我在一座森林,森林里有很多动物.然后有一只老鸟告诉我们,"我们有一座非常美丽的森林,

因此我们应该保护它,免受污染"所有的动物都赞成他.

但是第二天,人们进入我们的森林,许多动物被逮捕.这些人要在我们的森林地上建造房子和公园.许多年老的树木被砍下,然后,突然间,一切都被夷平了.

我很震惊,接着突然大哭起来.我在半夜醒来,原来只是个梦.

1. a big headache令人头痛的事情

2. a fraction of 一部分

3. a matter of concern 焦点

4. a series of 一系列,一连串above all 首先,尤其是

5. absent from不在,缺席

6. abundant in富于

7. account for 解释

8. accuse sb. of sth.控告

9. add to增加(add up to)

10. after all 毕竟,究竟

11. agree with同意

12. ahead of time / schedule提前

13. ahead of 在...之前(ahead of time 提前)

14. alien to与...相反

15. all at once 突然,同时

16. all but 几乎;除了...都

17. all of a sudden 突然

18. all over again 再一次,重新

19. all over 遍及

20. all right 令人满意的;可以

21. all the same 仍然,照样的

22. all the time 一直,始终

23. angry with sb. at/about sth.生气,愤怒

24. anxious about/for忧虑,担心

25. anything but 根本不

26. apart from 除...外

27. appeal to 吸引，申诉，请求

28. applicable to适用于

29. apply to适用

30. appropriate for/to适当,合适

Oceans becoming more acidicThe worlds oceans are slowly getting more acidic, say scientists.The researchers from California say the change is taking place in response to higher levels of carbon dioxide in the atmosphere.The lowering of the waters pH value is not great at the moment but could pose a serious threat to current marine life if it continues, they warn.Ken Caldeira and Michael Wickett, from the Lawrence Livermore National Laboratory, report their concerns in the journal Nature.Increasing use of fossil fuels means more carbon dioxide is going into the air, and most of it will eventually be absorbed by seawater.

Once in the water, it reacts to form carbonic acid.Scientists believe that the oceans have already become slightly more acidic over the last century.But these researchers have tried to predict what will happen in the future by combining what we know about the history of the oceans with computer models of climate change."This level of acidity will get much more extreme in the future if we continue releasing CO2 into the atmosphere," said Dr Caldeira."And we predicted amounts of future acidity that exceed anything we saw over the last several hundred million years, apart from perhaps after rare catastrophic events such as asteroid impacts."If carbon dioxide release continues unabated, ocean pH could be reduced by as much as 0.77 units, the authors warn.It is not absolutely clear what that means for marine life, however.

Most organisms live near the surface, where the greatest pH change would be expected to occur, but deep-ocean lifeforms may be more sensitive to pH changes.Coral reefs and other organisms whose skeletons or shells contain calcium carbonate may be particularly affected, the team speculate. They could find it much more difficult to build these structures in water with a lower pH.In recent years some people have suggested deliberately storing carbon dioxide from power stations in the deep ocean as a way of curbing global warming.But Dr Caldeira said that such a strategy should now be re-considered."Previously, most experts had looked at ocean absorption of carbon dioxide as a good thing - because in releasing CO2 into the atmosphere we warm the planet; and when CO2 is absorbed by the ocean, it reduces the amount of greenhouse warming.