English verb conjugation
COULD CENTRE

Regular verb: centre - centred - centred

Affirmation

Simple form	V-ing form
I could centre you could centre he could centre we could centre you could centre they could centre	I could be centring you could be centring he could be centring we could be centring you could be centring they could be centring
Perfect	V-ing perfect
I could have centred you could have centred he could have centred we could have centred you could have centred they could have centred	I could have been centring you could have been centring he could have been centring we could have been centring you could have been centring they could have been centring

Negation

Simple form	V-ing form
I couldn't centre you couldn't centre he couldn't centre we couldn't centre you couldn't centre they couldn't centre	I couldn't be centring you couldn't be centring he couldn't be centring we couldn't be centring you couldn't be centring they couldn't be centring
Perfect	V-ing perfect
I couldn't have centred you couldn't have centred he couldn't have centred we couldn't have centred you couldn't have centred they couldn't have centred	I couldn't have been centring you couldn't have been centring he couldn't have been centring we couldn't have been centring you couldn't have been centring they couldn't have been centring

Interrogative form

Simple form	V-ing form
could I centre? could you centre? could he centre? could we centre? could you centre? could they centre?	could I be centring? could you be centring? could he be centring? could we be centring? could you be centring? could they be centring?
Perfect	V-ing perfect
could I have centred? could you have centred? could he have centred? could we have centred? could you have centred? could they have centred?	could I have been centring? could you have been centring? could he have been centring? could we have been centring? could you have been centring? could they have been centring?

Interro-negative form

Simple form	V-ing form
couldn't I centre? couldn't you centre? couldn't he centre? couldn't we centre? couldn't you centre? couldn't they centre?	couldn't I be centring? couldn't you be centring? couldn't he be centring? couldn't we be centring? couldn't you be centring? couldn't they be centring?
Perfect	V-ing perfect
couldn't I have centred? couldn't you have centred? couldn't he have centred? couldn't we have centred? couldn't you have centred? couldn't they have centred?	couldn't I have been centring? couldn't you have been centring? couldn't he have been centring? couldn't we have been centring? couldn't you have been centring? couldn't they have been centring?