English verb conjugation
COULD TUG

Regular verb: tug - tugged - tugged

Affirmation

Simple form	V-ing form
I could tug you could tug he could tug we could tug you could tug they could tug	I could be tugging you could be tugging he could be tugging we could be tugging you could be tugging they could be tugging
Perfect	V-ing perfect
I could have tugged you could have tugged he could have tugged we could have tugged you could have tugged they could have tugged	I could have been tugging you could have been tugging he could have been tugging we could have been tugging you could have been tugging they could have been tugging

Negation

Simple form	V-ing form
I couldn't tug you couldn't tug he couldn't tug we couldn't tug you couldn't tug they couldn't tug	I couldn't be tugging you couldn't be tugging he couldn't be tugging we couldn't be tugging you couldn't be tugging they couldn't be tugging
Perfect	V-ing perfect
I couldn't have tugged you couldn't have tugged he couldn't have tugged we couldn't have tugged you couldn't have tugged they couldn't have tugged	I couldn't have been tugging you couldn't have been tugging he couldn't have been tugging we couldn't have been tugging you couldn't have been tugging they couldn't have been tugging

Interrogative form

Simple form	V-ing form
could I tug? could you tug? could he tug? could we tug? could you tug? could they tug?	could I be tugging? could you be tugging? could he be tugging? could we be tugging? could you be tugging? could they be tugging?
Perfect	V-ing perfect
could I have tugged? could you have tugged? could he have tugged? could we have tugged? could you have tugged? could they have tugged?	could I have been tugging? could you have been tugging? could he have been tugging? could we have been tugging? could you have been tugging? could they have been tugging?

Interro-negative form

Simple form	V-ing form
couldn't I tug? couldn't you tug? couldn't he tug? couldn't we tug? couldn't you tug? couldn't they tug?	couldn't I be tugging? couldn't you be tugging? couldn't he be tugging? couldn't we be tugging? couldn't you be tugging? couldn't they be tugging?
Perfect	V-ing perfect
couldn't I have tugged? couldn't you have tugged? couldn't he have tugged? couldn't we have tugged? couldn't you have tugged? couldn't they have tugged?	couldn't I have been tugging? couldn't you have been tugging? couldn't he have been tugging? couldn't we have been tugging? couldn't you have been tugging? couldn't they have been tugging?