English verb conjugation
COULD TOOTH

Regular verb: tooth - toothed - toothed

Affirmation

Simple form	V-ing form
I could tooth you could tooth he could tooth we could tooth you could tooth they could tooth	I could be toothing you could be toothing he could be toothing we could be toothing you could be toothing they could be toothing
Perfect	V-ing perfect
I could have toothed you could have toothed he could have toothed we could have toothed you could have toothed they could have toothed	I could have been toothing you could have been toothing he could have been toothing we could have been toothing you could have been toothing they could have been toothing

Negation

Simple form	V-ing form
I couldn't tooth you couldn't tooth he couldn't tooth we couldn't tooth you couldn't tooth they couldn't tooth	I couldn't be toothing you couldn't be toothing he couldn't be toothing we couldn't be toothing you couldn't be toothing they couldn't be toothing
Perfect	V-ing perfect
I couldn't have toothed you couldn't have toothed he couldn't have toothed we couldn't have toothed you couldn't have toothed they couldn't have toothed	I couldn't have been toothing you couldn't have been toothing he couldn't have been toothing we couldn't have been toothing you couldn't have been toothing they couldn't have been toothing

Interrogative form

Simple form	V-ing form
could I tooth? could you tooth? could he tooth? could we tooth? could you tooth? could they tooth?	could I be toothing? could you be toothing? could he be toothing? could we be toothing? could you be toothing? could they be toothing?
Perfect	V-ing perfect
could I have toothed? could you have toothed? could he have toothed? could we have toothed? could you have toothed? could they have toothed?	could I have been toothing? could you have been toothing? could he have been toothing? could we have been toothing? could you have been toothing? could they have been toothing?

Interro-negative form

Simple form	V-ing form
couldn't I tooth? couldn't you tooth? couldn't he tooth? couldn't we tooth? couldn't you tooth? couldn't they tooth?	couldn't I be toothing? couldn't you be toothing? couldn't he be toothing? couldn't we be toothing? couldn't you be toothing? couldn't they be toothing?
Perfect	V-ing perfect
couldn't I have toothed? couldn't you have toothed? couldn't he have toothed? couldn't we have toothed? couldn't you have toothed? couldn't they have toothed?	couldn't I have been toothing? couldn't you have been toothing? couldn't he have been toothing? couldn't we have been toothing? couldn't you have been toothing? couldn't they have been toothing?