Question :

1.What is Digory tempted to do in Chap. 4?

 He wanted look at this cold ,empty silence and dark place.

2.Why does he do it? 

He wanted have a explore in the other world.

3.Does it seem like magic forced him to do it? 

As I know it is a  slight effect on him ,and the other side they want to have a look at the new world when they have this chance and have enough curiosity.

4.Are there reasons why he should (or shouldn't) have done what he did?

Yes ,there are two reasons,one of them was they all want win ,so when Digory said Polly was afraid to look at this place ,Poll agreed him to look round.The other reason was they didn't afraid the dangous ,they have the yellow ring which can take them  out of this world.

@TS 我回来啦，接着打卡呀