The experiment proved successful.(prove怎么可以加形容词?

完全正确!prove用法：(一)可作系动词,后接(to be)＋名词/形容词,构成系表结构,意“结果是…,证明是”,没有被动语态。The book proved (to be) interesting。(二)作实义动词用法。1、prove＋n。(作宾语),意“证明某事”,如：The scientist finally proved the fact。那位科学家最终证实了那个事实。2、prove＋that宾语从句 The fact proved that his statement was true。事实证明他的说法是正确的。欢迎探讨词法语法问题。