动词不定式的形式this painting is said to have been drawn by the girl ,为什么用to have been done 形式呢,能用一般过去式吗,改成it is said that the painting was written by the girl,两种什么区别,有没有改错

动词不定式的形式
this painting is said to have been drawn by the girl ,为什么用to have been done 形式呢,能用一般过去式吗,改成it is said that the painting was written by the girl,两种什么区别,有没有改错