在前面的文章中我們給大家介紹了一些比較常見的標點符號使用錯誤，不知道大家有沒有犯過這些比較基本的錯誤呢?希望大家有的話可以改正過來。這篇文章小編想來詳細地給大家說一下留學論文中關于逗號的正確使用方法。逗號的主要作用為了避免歧義且讓讀者的閱讀速度更快，它的主要用法如下：

　　用“逗號+連詞”來連接兩個單獨的句子

　　這里的句子必須是地位平等的兩個句子，這樣的連詞有如下7種：and,but,or,nor,so,for以及yet，逗號的作用是連接兩個獨立的句子，告訴讀者下面會開啟另一個句子，下面我們來練習一下：

　　The department sponsored a seminar on college survival skills and it also hosted a barbecue for new students.

　　修改后應該是這樣的：…skills,and..逗號前后是兩個獨立的句子，不加逗號會引起歧義。

　　當然這里也有例外，如果兩個單獨的句子都很短且不加逗號不會產生歧義，那么就可以不加逗號，比如：

　　The plane took off and we were on our way.

　　下面是留學生常犯的問題：

　　A good money manager controls expenses,and invests surplus dollars to meet future needs.

　　這個句子的問題在于and前后不是單獨的句子，所以不用加逗號。

　　副詞性短語開頭的句子其后加逗號與主句隔開

　　如果一個句子是以副詞性的短語或者從句開頭，就要在這部分之后加一個逗號，其作用是引出接下來的主句，讓我們看看下面的句子逗號應該加在哪里?

　　Near a small stream at the bottom of the canyon the park rangers discovered an abandoned mine.沒錯，應該加在canyon后面。

　　當然這種情況也有例外：如果副詞性的短語非常短且不加逗號不會導致歧義，就可以不加，如：

　　In no time we were at 2,800 feet.

　　用逗號連接一系列并列的詞、詞組或者從句

　　Bubbles of air,leaves,ferns,bits of wood and insects are often found trapped in amber.要在wood后面加逗號。

　　Langston Hughes’s poetry is concerned with racial pride,social justice and the diversity of the African American experience.要在justice后面加逗號。

　　并列的多個形容詞之間可用逗號連接

　　Roberto is a warm,gentle,affectionate father.

　　因為這三個形容詞是分開單獨修飾父親的，所以之間可用逗號隔開，當然最后的逗號可以用and代替。

　　如果連續(xù)的形容詞不能夠單獨修飾后面的名詞，那么之間不加任何東西，如：

　　Three large gray shapes moved slowly toward us.

　　非限定性成分可用逗號隔開

　　限定性成分是用來限制所修飾成分的意義，如果去掉被修飾成分的意思會發(fā)生改變，這種情況下不能加任何逗號，比如說：

　　The campers need clothes that are durable.

　　反之，如果非限定性成分和被修飾詞之間的關系不是那么緊密，它的作用是增加信息，如果去掉之后不影響被修飾成分的意思，如：

　　The campers need sturdy shoes,which are expensive.

　　The scientists,who represented eight different universities,met to review applications for the prestigious O’Hara Award.

　　上面兩句話的重點信息在主句上面，從句的內容去掉之后不影響被修飾的名詞在主句中的角色。除了定語從句，形容詞性詞組以及同位語詞組也遵循上面的規(guī)則：

　　The helicopter,with its million-candlepower spotlight illuminating the area,circled above.(with its million-candlepower spotlight illuminating the area為非限定性成分，去掉之后對helicopter影響不大)

　　過渡詞后面需要加逗號表達停頓

　　這類詞包括：however,therefore,moreover,for example,as a matter of fact,in other words等等。

　　Minh did not understand our language;moreover,he was unfamiliar with our customs.

　　(moreover前面必須是分號，后面加一個逗號)

　　插入性信息要用逗號隔開

　　Evolution,as far as we know,doesn’t work this way.

　　The bass weighed about twelve pounds,give or take a few ounces.

　　對比強烈的詞組要用逗號隔開

　　Unlike Robert,Celia loved dance contests.

　　一些習慣性的用法

　　1).在直呼以及Yes和No后面需要逗號：

　　Forgive me,Angela,for forgetting your birthday.

　　Yes,the loan will probably be approved.

　　2).反問句

　　The film was faithful to the book,wasn’t it?

　　3).直接引語中

　　In his“Letter from Birmingham Jail,”Martin Luther King Jr.wrote,“We know through painful experience that freedom is never voluntarily given by the oppressor;it must be demanded by the oppressed”

　　4).日期On December 12,1890,orders were sent out for the arrest of Sitting Bull.

　　5).地址John Lennon was born in Liverpool,England,in 1940.

　　6).人名后面緊跟的頭銜之間要用逗號隔開Sandra Belinsky,MD,has been appointed to the hospital board.(MD=Medicine Doctor)

　　7).數字中3,500(此處逗號讀成thousand)1,000,000(此處逗號讀成million)2,000,222,222(此處逗號讀成billion)

　　特殊情況下需要加逗號避免歧義

　　To err is human;to forgive,divine.這邊作者省略了is All of the catastrophes that we had feared might happen,happened.

　　以上就是為大家整理的關于留學論文中逗號的正確使用方法，接下來讓我們來看一些比較常見逗號使用錯誤，希望引起大家的重視。

　　1.下面這兩個是最常見的錯誤

　　Marie Curie discovered radium,and later applied her work on radioactivity to medicine.

　　Jake told us that his illness is serious,but that changes in his lifestyle can improve his chances for survival.

　　第一個句子中的and是用來并列兩個謂語動詞，第二個句子中的but是用來并列兩個賓語從句，所以兩個句子中的逗號必須都要去掉!

　　2.不要用逗號將動詞和其主語或者賓語隔開，大家來看兩個病句

　　Zoos large enough to give the animals freedom to roam,are becoming more popular.Maxine Hong Kingston writes,that many Chinese American families struggle“to figure out how the invisible world the emigrants built around our childhoods fits in solid America”

　　兩個句子的逗號都是多余的。

　　3.在進行列舉的時候，不要在第一個項目前或者最后一個項目后添加逗號

　　Other causes of asthmatic attacks are,stress,change in temperature,and cold air.Ironically,even novels that focus on horror,evil,and alienation,often have themes of spiritual renewal and redemption.

　　4.在限定性修飾語和被修飾成分之間，不要加逗號

　　Drivers,who think they own the road,make cycling a dangerous sport.

　　(兩個逗號都是多余的，有逗號語意很難理解。)

　　5.一個以狀語從句結束的句子中間不加逗號

　　Don’t visit Paris at the height of the tourist season,unless you have booked hotel reservations.(這邊的逗號多余)

　　6.其他常見的使用錯誤

　　a.Occasionally TV talk shows are performed live,but,more often they are taped.(but后面的逗號多余)

　　b.Although,the air was balmy,the water was too cold for swimming.(although后面的逗號多余)