句子的各個成分之間保持在人稱、性、數等方面的一致，這種關系稱為一致關系。英語中的一致表現為語法一致、意義一致和毗鄰一致三方面。

　　絕大多數謂語動詞在人稱和單復數上取決于主語的人稱和單復數。如：

　　The burnt child fears the fire.

　　Things are invented when the need is great enough.

　　有時謂語動詞的單復數取決于主語的單復數意義，而不是簡單地取決于主語的單復數形式，這在集合名詞作主語時尤其如此：當主語強調整體時，謂語動詞用單數;當主語強調構成集合的各個成員時，謂語動詞用復數。如：

　　The basketball team consists of 20 players.(指整個球隊)

　　The basketball team are having a bath now.(指籃球隊的隊員)

　　當主語是由連詞等連接的一個短語時，往往采取就近原則，即謂語動詞的單復數形式取決于最靠近它的名詞或代詞的單復數形式和意義。如：

　　Either the sweater or the shirts were a good buy.

　　Either the shirts or the sweater was a good buy.

　　1.謂語動詞根據主語意義及就近原則而定的情形：

　　⑴單復數形式相同的名詞用作主語時，要根據它們所含的數量概念來決定謂語動詞的單復數形式。如：

　　A sheep is running along the river.

　　Some sheep are running along the river.

　　常見的這些名詞有：aircraft， fish， means， sheep， species， works， Chinese， Japanese， swine等。

　　⑵可數的集體名詞，如果作為一個集合概念來看，它表示單數意義，就應該遵循語法一致的原則，動詞用單數形式;如果強調的是個體，它表示的就是復數意義，動詞用復數形式。如：

　　The audience was enormous.

　　The audience were greatly moved at the word.

　　常見的這些名詞有：army，audience，class，club，jury，public，school，staff，government，team等。

　　⑶當數學運算中的數詞作主語時，謂語動詞用單復數均可，但若用了plus， minus， multiplied或divide時，謂語動詞多用equals.

　　Two fours are eight.

　　6 multiplied by 3 equals 18.

　　Four from five leaves one.

　　⑷在強調句型“It is/was…that/who…”中，強調主語時，that/who引導的從句的謂語動詞的形式取決于被強調詞的單復數形式或其意義。

　　It is precisely the people who create history.

　　⑸“the minority/majority of 名詞”短語作主語時，謂語動詞的單復數形式取決于名詞的單復數形式。如：

　　The majority of students were on Ben‘s side.

　　⑹“all (any， some， a lot， lots， the rest， none， loads， the reminder和分數名詞短語)of 名詞“作主語時，若名詞為復數意義，謂語動詞用復數形式;否則用單數形式。

　　Half of them are here.

　　All the land is cultivated.

　　Tree fourths of the surface of the earth is sea.

　　⑺“…form(s) / kind(s) / type(s) of 名詞”作主語時，謂語動詞的單復數與form(s)等的單復數一致，此時，若名詞是不可數名詞，謂語動詞也要用復數形式。如：

　　This kind of book sells well.

　　Two kinds of salt have been proved to be harmful to human body.

　　⑻“plenty (part， half， rest等) 名詞”作主語時，謂語動詞與of后面的名詞的單復數形式一致。如：

　　Half of the guests were here.

　　⑼由并列連詞(or， either…or， neither…nor， not only…but (also)等)連接的并列成份作主語時，謂語動詞按就近原則與其保持一致。如：

　　Neither you nor I am right.

　　Either Jack or his sisters are going to the cinema.

　　⑽在“here， there”引導的結構中，如果有多于一個的主語，謂語動詞與鄰近的主語取得一致。如：

　　There are two books， a rule and a pen on the desk.

　　Here is a table， some chairs， and a few desks in the room.

　　⑾“the 形容詞或分詞”作主語時，若指一個人或抽象概念，謂語動詞用單數形式;若指一類人，謂語動詞用復數形式。如：

　　The deceased was his mother.

　　The good are demanding their ringhts.

　　⑿由as well as， as much as， no less than， rather than等連接的并列主語，在意義上更強調第一主語。根據語法一致的原則，動詞形式通常取決于第一主語的數和人稱。如：

　　I， as well as him， am ready for outing.

　　He as much as us is responsible for it.

　　2.謂語動詞用單數形式的情形：

　　⑴不定式短語、動名詞及名詞從句作主語時，謂語動詞用單數形式。如：

　　To become doctors is their ambition.

　　Reading without comprehension is no good.

　　What that country needs is more jobs and lower taxes.

　　⑵表示時 間、距離、重量、長度、價值等的名詞，不論單復數，當作主語時，謂語動詞均用單數形式。如：

　　Twenty years is a long period of his life.

　　Five thousand dollars is more than I can afford.

　　⑶用and連接的名詞或代詞前有every， each， no， many a等修飾時，謂語動詞用單數。如：

　　Every one of the figures was checked at least twice.

　　⑷事件、國名、機構名稱、書籍及其它作品的名稱作主語時，謂語動詞均用單數形式。

　　The United Nations was formed in 1945.

　　Great Expectation is a very famous novel.

　　⑸限定詞(each， every， one， many a， not only one， either， neither等)作主語或修飾主語時，謂語動詞一般是單數。如： 　　Each of the students has a studying plan.

　　Every cook praises his own broth.

　　⑹and連接的兩個名詞或代詞作主語時，如果指的是同一個人或指一種整體事物時，根據概念一致的原則，后面的動詞要用單數形式。特別是and前的名詞或代詞前有冠詞the，而and后的名詞或代詞前沒有冠詞the，須用單數謂語。

　　Ham and eggs is often preferred to hamburgers.

　　The manager and secretary was present at the meeting.

　　這類名詞還有：fish and chips， bread and butter，law and order，a cup and saucer，the needle and thread等。

　　⑺短語“a deal (amount， proportion， quantity) 不可數名詞”、“a portion (kind， series， species) of 名詞“作主語時，謂語動詞用單數。

　　A large amount of oil was spilt on the road.

　　A portion of goods has been transported to the city.

　　⑻“the number of …”作主語時，謂語動詞也用單數形式。如：

　　The number of students is increasing every year in the school.

　　3.謂語動詞用復數形式的情形：

　　當主語是下列情況時，謂語動詞只能用復數形式。

　　⑴由and或both…and…連接的短語作主語。(2.中的⑹例外)

　　Both he and I are good at English.

　　⑵常以復數形式出現的名詞作主語。如：clothes， pants， shears， riches， remains等。

　　⑶quantities后面的名詞無論是可數名詞的復數還是不可數名詞，謂語都用復數形式。如：

　　Large quantities of steam are used by modern industry in the generation of power.

　　⑷“a number (group等) of…”作主語。如：

　　A number of people are in the meeting room now.

　　⑸不可數名詞前有表示數量的復數名詞修飾。如：

　　Six hundred square meters of housing have been built.

　　⑹只能看作復數的集合名詞作主語。這類集合名詞有：cattle， poultry， youth， clergy， police，people， militia， vermin等。

　　The cattle were grazing at the foot of the hill.

　　⑺當兩個形容詞用and連接來修飾一個單數名詞，實指兩個事物時，謂語動詞用復數形式。如：

　　The third and the fourth page are missing.