I didn't eat anything
Desde o ano passado não comi nada.
I haven't eaten anything since last year.
— Ирония судьбы, или С легким паром! (1976)
I haven't eaten anything today yet.
I haven't eaten anything yet.
Eu não comi nada desde o café da manhã.
I haven't eaten anything since breakfast.
I didn't eat anything yesterday.
I didn't eat anything.
Não comi nada desde ontem de manhã.
I haven't eaten anything since yesterday morning.