英语中逗号的用法,我觉得词句中应该没有逗号啊?

题目

英语中逗号的用法,我觉得词句中应该没有逗号啊?
About the closest （that）any research has come to supporting the tiredness theory is to confirm that adults yawn more often on weekdays than at weekends,and that school children yawn more frequently in their first year at primary school than they do in kindergarten.
原文中没有that,我已经补充,但是觉得词句中应该没有逗号,逗号+and ,and 后面应该是个完整句,不应该是一个从句啊?如果解释链接平行结构的两个动词,那就应该没有逗号,

答案

and 后面的that从句是confirm的宾语从句,两个宾从并列的话,第二个从句的that不能省略