Question

Como paso una oración afirmativa a negativa en inglés , .

Answer 1

agregando "not" y aplicando un poco de gramática

+ She works in a Hospital (Ella trabaja en un Hospital)
- She doesn't work in a Hospital (Ella no trabaja en un Hospital)

+ He is in USA (El está en EE.UU)
- He isn't in USA (El no está en EE.UU)

IMPORTANTE:
is not ... isn't
are not ... aren't
do not ... don't
does not ... doesn't