Bacon and eggs is a very popular British breakfast.
Jack and Mary are in love with each other.
Both Tom and John are absent today.
3、在由or 或 nor 连接的并列结构中，动词单、复数形式一般与or 或 nor 后面的名词或代词保持一致。
He or his brothers are to blame for this.
Neither she nor you are mistaken.
4、not only...but also 连接的结构作主语时，动词的单、复数形式依据 but also 后的名词或代词。
Not only Fred but also his parents love this small pet dog.
Not only the boys but also their mother is very ill.