There __is__ a pen, two pencils and several books on the desk. =There __are__ two pencils , a pen and several books on the desk.
are__ several books , a pen and two pencils on the desk.
所谓概念一致原则是指谓语动词和主语一致不是取决于主语的语法形式, 而是其实际意义。
1.集合名词作主语, 动词可用单数, 也可以用复数。主要由句子的意思决定。强调整体谓语动词用单数；指全体人员时, 动词则用复数。这一类常见的集合名词有public, family, class, crowd, population, team, group。
His family __is__going out. (强调整体) His family __are__all music lovers. (强调成员)
2. 不定代词all, more, some, any, none, each作主语,谓语动词视情况而定。 All of the apples _are_rotten. 所有的苹果都烂了。 All of the apple _is_rotten. 整个苹果都烂了。 ** Each of us __has___ a book. We each __have__ a book.
3. a lot of ; plenty of; the rest of; half of; part of; majority of; percent of; one third of 在句子中加名词作主语的时候,谓语动词与of后面的名词保持一致。
Half of the students _have_finished their composition. Half of the apple _is_bad.
About 60 percent of the students in our school _are_boys. 4. 某些名词如people, police, cattle等,形式上是单数, 但意义上是复数, 谓语动词应用复数。people指“民族”时是例外。
The police are searching for a thief. The cattle are eating grass on the hill.
5. 复合不定代词作主语, 谓语动词要用单数，如someone ,somebody, something, anybody, anyone, anything, everybody, everyone, everything, nobody, no one, nothing Someone is asking for you. Nothing is found in the room.
6. 某些名词如clothes, trousers, shoes, glasses等, 通常只用其复数形式, 但当它们被a pair of 修饰时, 谓语动词用单数。如:
The pair of shoes is worn out. The shoes are worn out.
7. 某些名词以s结尾如maths, politics, physics, news, plastics 等，谓语动词应用单数。 Physics is a very interesting subject.
8. every... and every ...; each ... and each ...; no ... and no ... 在以上短语中and连接的单数名词, 整个短语在句中作主语时, 谓语动词常使用单数。
Each man and each woman is asked to attend.
Every boy and every girl in the class is diligent. No sound and no voice is heard.
9. 以a number of 作主语时, 谓语动词用复数; 以the number of 作主语时, 谓语动词用单数。 A number of new books are on the desk. The number of students in your class is 50.
10. 有些名词的单数和复数形式一样, 作主语的时候, 其谓语动词由上下文决定, 这一类名词有: means, works, deer, fish, sheep, Chinese, Japanese等。