Kwa kanuni za ki lugha, si fasihi (grammer) kuwa na "negative" mbili ndani ya sentensi moja au kuwa na "positive" mbili ndani ya sentensi moja i.e. sio fasihi kusema NO I DONT HAVE A BRAIN au NO I DONT HAVE SENSE. au YES I AM STUPID. Ni sahihi kusema Yes, I dont have a brain au Yes I dont have sense au NO I am stupid!