English verb conjugation
COULD TIN

Regular verb: tin - tinned - tinned

Affirmation

Simple form	V-ing form
I could tin you could tin he could tin we could tin you could tin they could tin	I could be tinning you could be tinning he could be tinning we could be tinning you could be tinning they could be tinning
Perfect	V-ing perfect
I could have tinned you could have tinned he could have tinned we could have tinned you could have tinned they could have tinned	I could have been tinning you could have been tinning he could have been tinning we could have been tinning you could have been tinning they could have been tinning

Negation

Simple form	V-ing form
I couldn't tin you couldn't tin he couldn't tin we couldn't tin you couldn't tin they couldn't tin	I couldn't be tinning you couldn't be tinning he couldn't be tinning we couldn't be tinning you couldn't be tinning they couldn't be tinning
Perfect	V-ing perfect
I couldn't have tinned you couldn't have tinned he couldn't have tinned we couldn't have tinned you couldn't have tinned they couldn't have tinned	I couldn't have been tinning you couldn't have been tinning he couldn't have been tinning we couldn't have been tinning you couldn't have been tinning they couldn't have been tinning

Interrogative form

Simple form	V-ing form
could I tin? could you tin? could he tin? could we tin? could you tin? could they tin?	could I be tinning? could you be tinning? could he be tinning? could we be tinning? could you be tinning? could they be tinning?
Perfect	V-ing perfect
could I have tinned? could you have tinned? could he have tinned? could we have tinned? could you have tinned? could they have tinned?	could I have been tinning? could you have been tinning? could he have been tinning? could we have been tinning? could you have been tinning? could they have been tinning?

Interro-negative form

Simple form	V-ing form
couldn't I tin? couldn't you tin? couldn't he tin? couldn't we tin? couldn't you tin? couldn't they tin?	couldn't I be tinning? couldn't you be tinning? couldn't he be tinning? couldn't we be tinning? couldn't you be tinning? couldn't they be tinning?
Perfect	V-ing perfect
couldn't I have tinned? couldn't you have tinned? couldn't he have tinned? couldn't we have tinned? couldn't you have tinned? couldn't they have tinned?	couldn't I have been tinning? couldn't you have been tinning? couldn't he have been tinning? couldn't we have been tinning? couldn't you have been tinning? couldn't they have been tinning?