Why is this sentence correct :
You are more interesting than she.
It should be : You are more interesting than her.
Can you explain me, why is the second sentence grammatically incorrect..
It's a matter of using the correct pronoun case.
You are more interesting than she [is] where [is] is understood.
The case needs to be nominative. We use objective case when action is happening ON the object ..for example HER WALLET is heavier than MINE.