謝謝愚教授的批改！多費心了！

He might be the first person who mentioned that we should study science through observation and experiments in medieval times.

-- Where is the best place in the sentence for medieval times?
 
He might be the first person in Medieval Times ...?

this one is good.
or
mentioned in medieval times that ...?
or
we should study science in medieval times ...?

medieval times --> Medieval Times (noun for history period)

Anterior to Galileo, scholars believed .... -- Can you find a sentence that uses anterior the same way in which you use it?

No，I could not. 牢記在心。 

 

He carried two different sized stones which dropped on floor at the same time.

--

1. check the English definition for floor and ground
2. 他拎了兩塊大小不同的石頭。兩快石頭同時掉到樓板上了?

floor不對。那能用ground嗎？還是必須the earth？

It showed  his friends who went to see the experient with him that Aristotle was wrong.

-- It or Galileo showed to his friend that ...?

應該changed to Galileo（He）。

It was the spirit,  which Galileo testified our judgement and theories through nature directly, that led to ... --> It was the spirit, in which Galileo testified our judgement and theories through nature directly, that led to ...

怎麽記住這個in which呢。該讀哪部分語法，我可惡補一下？

謝謝愚教授！！！