用间接引语表达某人过去的观点时,从句时态变化吗?比如说,The professor said he is/was right?

用间接引语表达某人过去的观点时,从句时态变化吗?
比如说,The professor said he is/was right?

一般情况下,从句时态跟着主句时态改变.
e.g.The professor said he was right.
但有一种特殊情况,即在陈述客观事实时,用一般现在时.
e.g.The professor said the earth goes around the sun.