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