强调句。It was ... that...不过整句话有点不太规范，一般强调这种方式状语的比较少。原句可恢复成So much was learnt about the interior of the earth from the study of these. 从这些的研究中我们了解了很多关于地球内部的知识。...
It was from the study of these that so much was learnt about the interior of the earth.这是一个强调句型。So much主语 was learnedabout谓语 theinteriorof the earth 宾语from the studyo...
