Conjugação do verbo inglês
COULD SING

Verbo irregular: sing - sang - sung

Afirmação

Forma simple	Forma com V-ing
I could sing you could sing he could sing we could sing you could sing they could sing	I could be singing you could be singing he could be singing we could be singing you could be singing they could be singing
Perfeito	Perfeito com V-ing
I could have sung you could have sung he could have sung we could have sung you could have sung they could have sung	I could have been singing you could have been singing he could have been singing we could have been singing you could have been singing they could have been singing

Negação

Forma simple	Forma com V-ing
I couldn't sing you couldn't sing he couldn't sing we couldn't sing you couldn't sing they couldn't sing	I couldn't be singing you couldn't be singing he couldn't be singing we couldn't be singing you couldn't be singing they couldn't be singing
Perfeito	Perfeito com V-ing
I couldn't have sung you couldn't have sung he couldn't have sung we couldn't have sung you couldn't have sung they couldn't have sung	I couldn't have been singing you couldn't have been singing he couldn't have been singing we couldn't have been singing you couldn't have been singing they couldn't have been singing

Forma interrogativa

Forma simple	Forma com V-ing
could I sing? could you sing? could he sing? could we sing? could you sing? could they sing?	could I be singing? could you be singing? could he be singing? could we be singing? could you be singing? could they be singing?
Perfeito	Perfeito com V-ing
could I have sung? could you have sung? could he have sung? could we have sung? could you have sung? could they have sung?	could I have been singing? could you have been singing? could he have been singing? could we have been singing? could you have been singing? could they have been singing?

Forma interro-Negação

Forma simple	Forma com V-ing
couldn't I sing? couldn't you sing? couldn't he sing? couldn't we sing? couldn't you sing? couldn't they sing?	couldn't I be singing? couldn't you be singing? couldn't he be singing? couldn't we be singing? couldn't you be singing? couldn't they be singing?
Perfeito	Perfeito com V-ing
couldn't I have sung? couldn't you have sung? couldn't he have sung? couldn't we have sung? couldn't you have sung? couldn't they have sung?	couldn't I have been singing? couldn't you have been singing? couldn't he have been singing? couldn't we have been singing? couldn't you have been singing? couldn't they have been singing?