prove作"证明是;结果是;事实说明"解时,可用作连系动词.
连系动词解释起来有点复杂,最最常见的连系动词是“is/am/are”,其他连系动词的用法与"be"动词用法类似.
1.一般情况下,句子结构是是谓语+宾语,但是连系动词后面加的不叫宾语,叫表语.连系动词+表语叫做“系表结构”（参考百度百科'连系动词"）
2.常见的连系动词有：be,look,sound,taste,smell,seem,appear,prove,keep,remain,continue,become,get,turn等等（参考百度百科'连系动词"）
3.表语通常是名词,形容词,动词不定式,介词短语或副词,从句来充当.
名词作表语：His efforts,however,proved a failure
形容词作表语：The medicine proved satisfactory.
不定式作表语：Einstein's theory proved to be correct.
介词短语作表语：Perhaps this book will prove of some use to you in your studies.
等等.
详细了解连系动词,请参考语法书中的详细解释,谢谢您的帮助。还想问问 They died young. 是系表结构吗？此句摘自 “They worked until exhausted, lived with few protections and died young.”they die young这句话我也见过，从语感角度说觉得听得很顺耳，不别扭，但是我个人认为，单从语法角度说，这句话是不符合正常语法的，应该说die at a young age。这是我个人的认为，你可以问下你们英语老师，如果确实是不符合语法的，就当固定用法记吧。比如ibm的广告词还说think different.这从语法角度说也不对啊，应该是think differently.我个人认为die不是系动词或其他有特殊用法的动词，就是一个一般的动词，但是确保起见，你再问下你们英语老师。