I could survive you could survive he could survive we could survive you could survive they could survive
V-ing form
I could be surviving you could be surviving he could be surviving we could be surviving you could be surviving they could be surviving
Perfect
I could have survived you could have survived he could have survived we could have survived you could have survived they could have survived
V-ing perfect
I could have been surviving you could have been surviving he could have been surviving we could have been surviving you could have been surviving they could have been surviving
Negation
Simple form
I couldn't survive you couldn't survive he couldn't survive we couldn't survive you couldn't survive they couldn't survive
V-ing form
I couldn't be surviving you couldn't be surviving he couldn't be surviving we couldn't be surviving you couldn't be surviving they couldn't be surviving
Perfect
I couldn't have survived you couldn't have survived he couldn't have survived we couldn't have survived you couldn't have survived they couldn't have survived
V-ing perfect
I couldn't have been surviving you couldn't have been surviving he couldn't have been surviving we couldn't have been surviving you couldn't have been surviving they couldn't have been surviving
Interrogative form
Simple form
could I survive? could you survive? could he survive? could we survive? could you survive? could they survive?
V-ing form
could I be surviving? could you be surviving? could he be surviving? could we be surviving? could you be surviving? could they be surviving?
Perfect
could I have survived? could you have survived? could he have survived? could we have survived? could you have survived? could they have survived?
V-ing perfect
could I have been surviving? could you have been surviving? could he have been surviving? could we have been surviving? could you have been surviving? could they have been surviving?
Interro-negative form
Simple form
couldn't I survive? couldn't you survive? couldn't he survive? couldn't we survive? couldn't you survive? couldn't they survive?
V-ing form
couldn't I be surviving? couldn't you be surviving? couldn't he be surviving? couldn't we be surviving? couldn't you be surviving? couldn't they be surviving?
Perfect
couldn't I have survived? couldn't you have survived? couldn't he have survived? couldn't we have survived? couldn't you have survived? couldn't they have survived?
V-ing perfect
couldn't I have been surviving? couldn't you have been surviving? couldn't he have been surviving? couldn't we have been surviving? couldn't you have been surviving? couldn't they have been surviving?