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