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