三、谓语动词
(一) 谓语动词的主谓一致
①、主谓分割原则
例1：To the citizens of the United States, the bald eagle,
A
America's national bird, symbolize strength and freedom.
B C D
分析：C错，应改为symbolizes。主语谓语用逗号分割开，主语the bald eagle为单数，谓语动词也应该用单数形式。
②、与后者一致原则
not…but, 强调but后面的名词，
not only…but also
③、与前者一致原则
名词+with/together with/as well as/including+复数名词，谓语用is,
中心词在前面，谓语动词应该与前面的名词保持一致
例：The athlete, together with his coach and
A B C
several relatives, are traveling to the Olympic Games.
D
分析：D错，与谓语动词与the athlete 保持一致，改为is
④、就近原则
or, either…or, neither…nor,
单数名词+or+复数名词+are
如果把句子变为一般疑问句，也就是把be动词提到前面，那么变为is
所以注意一点： 如果是陈述句，靠后面近，用复数
如果是疑问句，靠前面近，用单数
例：The structure or behavior of many protozoans are
A B
amazingly complex for single-celled animals.
C D
分析：A错，应改为and。从谓语动词是复数形式判断，主语应该为复数，or连接两个名词时动词和后面的名词保持一致，behavior是用单数形式，因此只有改为并列连词and才能使主谓在数上保持一致。
⑤定语从句主语就近原则
There are five apples that are red.
apples是复数，因此从句谓语动词是复数。
例：A rocket burns propellant rapidly and most rockets
A
carry a supply that last just a few seconds.
B C D
分析：D错，应改为lasts。从句的逻辑主语a supply为单数，其谓语动词应为单数形式。