English verb conjugation
COULD TANK

Regular verb: tank - tanked - tanked

Affirmation

Simple form	V-ing form
I could tank you could tank he could tank we could tank you could tank they could tank	I could be tanking you could be tanking he could be tanking we could be tanking you could be tanking they could be tanking
Perfect	V-ing perfect
I could have tanked you could have tanked he could have tanked we could have tanked you could have tanked they could have tanked	I could have been tanking you could have been tanking he could have been tanking we could have been tanking you could have been tanking they could have been tanking

Negation

Simple form	V-ing form
I couldn't tank you couldn't tank he couldn't tank we couldn't tank you couldn't tank they couldn't tank	I couldn't be tanking you couldn't be tanking he couldn't be tanking we couldn't be tanking you couldn't be tanking they couldn't be tanking
Perfect	V-ing perfect
I couldn't have tanked you couldn't have tanked he couldn't have tanked we couldn't have tanked you couldn't have tanked they couldn't have tanked	I couldn't have been tanking you couldn't have been tanking he couldn't have been tanking we couldn't have been tanking you couldn't have been tanking they couldn't have been tanking

Interrogative form

Simple form	V-ing form
could I tank? could you tank? could he tank? could we tank? could you tank? could they tank?	could I be tanking? could you be tanking? could he be tanking? could we be tanking? could you be tanking? could they be tanking?
Perfect	V-ing perfect
could I have tanked? could you have tanked? could he have tanked? could we have tanked? could you have tanked? could they have tanked?	could I have been tanking? could you have been tanking? could he have been tanking? could we have been tanking? could you have been tanking? could they have been tanking?

Interro-negative form

Simple form	V-ing form
couldn't I tank? couldn't you tank? couldn't he tank? couldn't we tank? couldn't you tank? couldn't they tank?	couldn't I be tanking? couldn't you be tanking? couldn't he be tanking? couldn't we be tanking? couldn't you be tanking? couldn't they be tanking?
Perfect	V-ing perfect
couldn't I have tanked? couldn't you have tanked? couldn't he have tanked? couldn't we have tanked? couldn't you have tanked? couldn't they have tanked?	couldn't I have been tanking? couldn't you have been tanking? couldn't he have been tanking? couldn't we have been tanking? couldn't you have been tanking? couldn't they have been tanking?