"Eats more then he could eat"....

1. A pig cannot be called he, pigs are refered to as "it"

2. "could" in the sentence is supposed to be can

3. "then" is wrong, it should be "than"

"He is the worst king in Nepali history"

1. He was not He is.

2. In the history of Nepal, Not in Nepali history. 

Go back and re-visit My English book.

PS: Please let me know if I made any mistake editing this comment.