A negative sentence is formed by adding not
(or -n't in the shortened form)
· to an auxiliary (have, be, do, must, can...).
· to be and have when they are used as
main verbs.
Example: I am at work.
I am not (I'm not) at work.
You are my best friend.
You are not (aren't) my best friend.
He has enough money.
He has not (hasn't) enough money.
Insusceptible