all指人时,动词用复数;all指物时,动词用单数.例如:"All are present and all is going well." 所有人全部到场了,一切进展顺利

由all of,most of,a lot of,some of,none of,plenty of ,the rest 等 + 名词作主语时,谓语动词的单数形式应与名词一致.例如：

None of this meat is fit to eat.

All of the research work was designed by the chief engineer.