oys with their father 这后面跟 are 和动词原形 （ 就远原则）
boys or their father 后面跟is 或动词第三人称单数（ 就近原则）
记住：
主语后接有with ,along with ,together with , as well as , no less than , more than , including ,besides , like , except , but 等词或短语时,谓语动词的数由主语的单,复数形式决定,即“就远原则”如 No one but I is mistaken .
1 由either … or … , neither … nor … , not only … but also … , not … but ….., 或or连接两个并列主语时,谓语动词与较近的主语保持一致.即‘就近原则’.
2 There be …和 here be …. 中的BE 与就近的主语在数上保持一致. 即‘ 就近原则’.
3 由and 连接的两个名词作主语, 如果是指同一概念（即AND 后没有冠词） ,谓语动词用单数形式.如
The teacher and writer is coming to ourschool next week.. 那位老师兼作家下周要来我们学校.
区别：The teacherand the writer are coming to our school next week..
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