一个关于完成时态的问题

xiaoyaohfb123

Ringing in the ear has been regarded as a sign of approaching death.
Ringing in the ear is regarded as a sign of approaching death.
这两句有什么区别吗

吴二

区别：第一个，表示一直以来被认为是，说不定现在就有新证据来把它给证伪了。
          第二个，表示被认为是客观事实。