这是英语主谓一致的原则之一,叫做就前原则.也就是由with连接的两个或以上的并列的人或事物作主语时,句子的谓语动词要根据with前面的变化.如：He with his parents goes to the theatre every Sunday.
除with外,together with,along with,as well as,besides,except,except for,but,apart from,including等都遵循此原则.
希望对你有所帮助.