Question

change into negative you are sometimes foolish.

Answer 1

U are sometimes not foolish

Answer 2

hey there !!
$\textbf{possitive\: sentence}$:-
☯️ you are sometimes foolish.
$\textbf{change \:into\: negative}$:-
☯️ you are not sometimes foolish .

$\underline{rules\: of\: formation\: of\: affirmative \:sentence\: into \:negative\: sentence}$.

☯️use not after helping verb in affirmative sentence.