1.Both you and I are students. both...and...“两者都...”,连接名词或代词作主语时,谓语动词用复数形式,不受‘就近原则’的限制。
Both Li Ming and Wei Hua are good at English.
2.and 连接两个成分作主语时,谓语要用复数形式。
You and she are on duty today.
3.采用就近原则的情况:当连词或连词短语连接两个成分,而重点强调的是“其中之一”的时候,要采用就近原则。
Both...and作为关联并列连词,它通常应连接两个相同性质的句子成分,但有时后一成分可能省略与前一成分相同,意思分别为“...和...都”、“不但... 而且... ”、“既... 又...”,
用法如下:

1、“...和...都”,连接两个成分作主语,谓语总是用复
例:
Both she and Lucy were pleased with the cat..她和露西都喜欢这只猫。
You and she are on duty today.
你和她今天是值日生。
2、“不但... 而且... ”起连接词作用,连接两个并列成
例:
She both speaks and writes English。
她不仅会说英语,而且还会写。

3、“既... 又..
连接的两个成分必须在形式、时态、词性等方面完全一致,可以是形容词、名词、动词和句子等,一般语法结构是:
both+形容词+and+形容词
例:
The results of the research are both impressive and alarming.研究结果既令人印象深刻又令人担忧。
both+名词+and+名词
例:
Both the movie and the actor were good.
电影和演员都很好。
both+动词+and+动词
例:
Peter both likes and recommends the movie.皮特既喜欢又推荐这部电影。