Conjugación del verbo inglés
COULD UPGRADE

Verbo regular: upgrade - upgraded - upgraded

Afirmación

Forma simple	Forma con V-ing
I could upgrade you could upgrade he could upgrade we could upgrade you could upgrade they could upgrade	I could be upgrading you could be upgrading he could be upgrading we could be upgrading you could be upgrading they could be upgrading
Perfecto	Perfecto con V-ing
I could have upgraded you could have upgraded he could have upgraded we could have upgraded you could have upgraded they could have upgraded	I could have been upgrading you could have been upgrading he could have been upgrading we could have been upgrading you could have been upgrading they could have been upgrading

Negación

Forma simple	Forma con V-ing
I couldn't upgrade you couldn't upgrade he couldn't upgrade we couldn't upgrade you couldn't upgrade they couldn't upgrade	I couldn't be upgrading you couldn't be upgrading he couldn't be upgrading we couldn't be upgrading you couldn't be upgrading they couldn't be upgrading
Perfecto	Perfecto con V-ing
I couldn't have upgraded you couldn't have upgraded he couldn't have upgraded we couldn't have upgraded you couldn't have upgraded they couldn't have upgraded	I couldn't have been upgrading you couldn't have been upgrading he couldn't have been upgrading we couldn't have been upgrading you couldn't have been upgrading they couldn't have been upgrading

Forma interrogativa

Forma simple	Forma con V-ing
could I upgrade? could you upgrade? could he upgrade? could we upgrade? could you upgrade? could they upgrade?	could I be upgrading? could you be upgrading? could he be upgrading? could we be upgrading? could you be upgrading? could they be upgrading?
Perfecto	Perfecto con V-ing
could I have upgraded? could you have upgraded? could he have upgraded? could we have upgraded? could you have upgraded? could they have upgraded?	could I have been upgrading? could you have been upgrading? could he have been upgrading? could we have been upgrading? could you have been upgrading? could they have been upgrading?

Forma interro-negativa

Forma simple	Forma con V-ing
couldn't I upgrade? couldn't you upgrade? couldn't he upgrade? couldn't we upgrade? couldn't you upgrade? couldn't they upgrade?	couldn't I be upgrading? couldn't you be upgrading? couldn't he be upgrading? couldn't we be upgrading? couldn't you be upgrading? couldn't they be upgrading?
Perfecto	Perfecto con V-ing
couldn't I have upgraded? couldn't you have upgraded? couldn't he have upgraded? couldn't we have upgraded? couldn't you have upgraded? couldn't they have upgraded?	couldn't I have been upgrading? couldn't you have been upgrading? couldn't he have been upgrading? couldn't we have been upgrading? couldn't you have been upgrading? couldn't they have been upgrading?