"He takes the best care of his parents " make it positive- He has taken best care of his Parents
Explanation:
A positive sentence (PS) is that which tells you that something is so.
For Example: Parmit is running,Everyone is in the garden,It is very cloudy,the fridge is empty.
A Negative sentence is that sentence which tells you something is not so is called a negative sentence (NS).
IA negative sentence contains a negative words like not, never, no, no one, nobody, none, or a negative verb like isn’t or can’t or won’t.
For Example:He is not walking,We should never tell lies,There is no one in the house,the fridge is not empty
So ,we can rewrite the sentence as "He takes the best care of his parents " as -"He has taken best care of his Parents"