如果句子主语是单数,则对应动词的单数形式。如果主语是复数,动词需与主语保持一致性
例:She lives in China. (三单)
More people live in Asia than in any other continent. (主语复数动词原型)
当句子的主语结构复杂时,动词和主语的主体部分保持一致
例:Many leading members of the opposition party have criticised the delay. (members和have对应)
The only excuse that he gave for his actions was that he was tired. (excuse和was对应)
当主语跟在动词后面,则动词必须跟主语保持一致
例:Displayed on the board were the exam results. (与The exam results were displayed ...进行比较)
从句作主语时,动词是三单形式
例:To keep these young people in prison is inhuman.
Having overall responsibility for the course means that I have a lot of meetings.
Whoever took them remains a mystery.
然而,what从句作主语时,动词后的主名词为单数,则动词为单数形式,主名词为复数,则动词为三单或原型
例:What worries us is the poor selection process.
What is needed are additional resources. (更口语化则是...needed is...)
某些名词虽然是单数形态,但指的是复数个体,其对应的动词可用单数或复数形式。这种名词成为集合名词
例:The council has (or have) postponed a decision on the new road.
通常当主语是一个机构或组织这种可以看成是一个整体时,对应单数动词,如果是由很多个个体组成的团体,对应复数动词。在正式书写尤其是学术报告中,动词常采用单数形式。
某些语境中必须正确选择动词的单复数形式
例:The committee usually raise their hands to vote 'Yes'. (因为举手的是一个个成员,所以不能用The committee usually raised its hands...)
The school is to close next year. (因为关掉的是学校这个机构,而非单指里面的学生或雇员,所以不能是The school are to close...)
当主语名词用-s结尾但是指的是一个单数个体,则动词对应的是单数形式,此类名词有countries, newspapers, titles of books, films等等
例:At this time of the year the Netherlands is one hour ahead of the UK.
The Machine Gunners was one of Robert Westall's most successful books.
'Daps' is the word used in the south-west of the country for sports shoes.
句中出现any of, each of, either of, neither of或none of,以及一个复数名词/代词的时候,可以用单数或复数动词
例:I don't think any of them knows(或know)where the money is hidden.
Neither of the French athletes has (或have)won this year.
句中出现a/the majority of, a number of, a lot of, plenty of, all (of)或some (of),以及一个复数名词/代词时候,用复数动词。(主语the number of对应单数动词)
例:A number of refugees have been turned back at the border.
The number of books in the library has risen to over five million.
One of和一个复数名词/代词后面跟单数动词,然而one of+复数名词/代词+who后面即可跟单数也可跟复数动词,复数动词会更加符合语法习惯。
例:One of the reasons I took the job was that I could work from home.
He's the one of those teachers who insist/insists on pupils sitting silently in class.
句中出现any of, none of, the majority, a lot of, plenty of, all (of), some (of)和一个不可数名词时,用单数动词
例:All the furniture was destroyed in the fire.
None of the equipment appears to be damaged.
句中出现every或each和一个单数名词或坐标名词(x,y),用单数名词
例:Every room looks over the harbour.
Every boy and girl takes part in the activity.
Each child has drawn a picture
注意The children have each drawn a picture.
句中出现everyone, everybody, everything (及类似的以any-, some-和no-打头的单词),用单数名词
例:Practically everyone thinks that Phil should be given the job.
当两个或两个以上的个体构成主语时,通常用复数动词
例:Ingrid and Tobias are moving back to Australia.
但是,当复数项目构成的主语视为一个单独个体的时候,可以用单数动词
例:The lorry, its cargo and passengers weighs around 35 tonnes. (或...weigh...)
当主语由两个或两个以上的个体用(either)...or...或(neither)...nor的形式构成,则最后个体为单数时对应单数动词(非正式英语汇总某些时候可以用复数动词),最后个体为复数时对应复数动词
例:Either the station or the cinema is a goodd place to meet. (不正式说法中可以用...are...)
The President or his representatives are to attend the meeting.
如果最后的个体是单数,它之前的都是复数,可用单数或复数动词
例:Either the teachers or the principal is to blame for the accident. (或...are to blame...)
在there+be/have句型中,单数动词对应单数或不可数名词,复数动词对应复数名词。然而,在口语中通常用单数形式缩写there's对应复数名词
例:Over the last few years there have been many improvements in car safety.
There's been lots of good films on lately. (或There've been...)
某些名词通常以复数形式出现,对应复数动词,此类名词除以下示例外还有belongings, clothes, congratulations, goods, outskirts, overheads, particulars(译为信息),premises(译为建筑物),riches, savings, stairs, surroundings, thanks
例:The company's earnings have increased for the last five years.
whereabouts既可以跟单数也可以跟复数动词,police,people和staff通常对应复数动词
例:Police believe that Thomas is in Brazil, although his exact whereabouts are/is unknown.
Staff say that the new computer system has led to greater levels of stress in their work.
复数名词data,media(单数为datum, medium)通常对应单数动词,但是在学术报告这种正式书写中,建议用复数动词。其它复数名词例如criteria和phenomena(单数为criterion, phenomenon)通常用复数动词
例:All the data is available for public inspection. (或者...are available...)
I agree that the criteria are not of equal importance. (或者...the criteria is not...)
某些s结尾的不可数名词看上去像复数名词,但是作主语时对应单数动词,除以下示例外此类名词还有means (译为方法或钱),economics, linguistics, mathematics, phonetics, physics, politics, statistics, athletics, gymnastics, diabetes, measles, rabies
例:The news from the Middle East seems very encouraging.
句中出现尺寸、数量等的名词短语,通常用单数动词,补语为单数名词短语时(例如a long time),必须用单数动词
例:Only three metres separates the runners in first and second places. (比...separate更合适)
Three hours seems a long time to take on the homework. (不能是Three hours seem...)
复杂结构的主语是百分比或分数时,动词与最近的名词保持一致
例:An inflation rate of only 2% makes a difference to exports.
About 50%/half of the houses need major repairs.
其中,如果出现的单数名词即可以作为整体又可以作为许多个体看待时,动词既可以是单数也可以是复数
例:Some 80% of the electorate is expected to vote. (或...are expected...)