Conjugação do verbo inglês
COULD PERFORM

Verbo regular: perform - performed - performed

Afirmação

Forma simple	Forma com V-ing
I could perform you could perform he could perform we could perform you could perform they could perform	I could be performing you could be performing he could be performing we could be performing you could be performing they could be performing
Perfeito	Perfeito com V-ing
I could have performed you could have performed he could have performed we could have performed you could have performed they could have performed	I could have been performing you could have been performing he could have been performing we could have been performing you could have been performing they could have been performing

Negação

Forma simple	Forma com V-ing
I couldn't perform you couldn't perform he couldn't perform we couldn't perform you couldn't perform they couldn't perform	I couldn't be performing you couldn't be performing he couldn't be performing we couldn't be performing you couldn't be performing they couldn't be performing
Perfeito	Perfeito com V-ing
I couldn't have performed you couldn't have performed he couldn't have performed we couldn't have performed you couldn't have performed they couldn't have performed	I couldn't have been performing you couldn't have been performing he couldn't have been performing we couldn't have been performing you couldn't have been performing they couldn't have been performing

Forma interrogativa

Forma simple	Forma com V-ing
could I perform? could you perform? could he perform? could we perform? could you perform? could they perform?	could I be performing? could you be performing? could he be performing? could we be performing? could you be performing? could they be performing?
Perfeito	Perfeito com V-ing
could I have performed? could you have performed? could he have performed? could we have performed? could you have performed? could they have performed?	could I have been performing? could you have been performing? could he have been performing? could we have been performing? could you have been performing? could they have been performing?

Forma interro-Negação

Forma simple	Forma com V-ing
couldn't I perform? couldn't you perform? couldn't he perform? couldn't we perform? couldn't you perform? couldn't they perform?	couldn't I be performing? couldn't you be performing? couldn't he be performing? couldn't we be performing? couldn't you be performing? couldn't they be performing?
Perfeito	Perfeito com V-ing
couldn't I have performed? couldn't you have performed? couldn't he have performed? couldn't we have performed? couldn't you have performed? couldn't they have performed?	couldn't I have been performing? couldn't you have been performing? couldn't he have been performing? couldn't we have been performing? couldn't you have been performing? couldn't they have been performing?