I could tambour you could tambour he could tambour we could tambour you could tambour they could tambour
V-ing form
I could be tambouring you could be tambouring he could be tambouring we could be tambouring you could be tambouring they could be tambouring
Perfect
I could have tamboured you could have tamboured he could have tamboured we could have tamboured you could have tamboured they could have tamboured
V-ing perfect
I could have been tambouring you could have been tambouring he could have been tambouring we could have been tambouring you could have been tambouring they could have been tambouring
Negation
Simple form
I couldn't tambour you couldn't tambour he couldn't tambour we couldn't tambour you couldn't tambour they couldn't tambour
V-ing form
I couldn't be tambouring you couldn't be tambouring he couldn't be tambouring we couldn't be tambouring you couldn't be tambouring they couldn't be tambouring
Perfect
I couldn't have tamboured you couldn't have tamboured he couldn't have tamboured we couldn't have tamboured you couldn't have tamboured they couldn't have tamboured
V-ing perfect
I couldn't have been tambouring you couldn't have been tambouring he couldn't have been tambouring we couldn't have been tambouring you couldn't have been tambouring they couldn't have been tambouring
Interrogative form
Simple form
could I tambour? could you tambour? could he tambour? could we tambour? could you tambour? could they tambour?
V-ing form
could I be tambouring? could you be tambouring? could he be tambouring? could we be tambouring? could you be tambouring? could they be tambouring?
Perfect
could I have tamboured? could you have tamboured? could he have tamboured? could we have tamboured? could you have tamboured? could they have tamboured?
V-ing perfect
could I have been tambouring? could you have been tambouring? could he have been tambouring? could we have been tambouring? could you have been tambouring? could they have been tambouring?
Interro-negative form
Simple form
couldn't I tambour? couldn't you tambour? couldn't he tambour? couldn't we tambour? couldn't you tambour? couldn't they tambour?
V-ing form
couldn't I be tambouring? couldn't you be tambouring? couldn't he be tambouring? couldn't we be tambouring? couldn't you be tambouring? couldn't they be tambouring?
Perfect
couldn't I have tamboured? couldn't you have tamboured? couldn't he have tamboured? couldn't we have tamboured? couldn't you have tamboured? couldn't they have tamboured?
V-ing perfect
couldn't I have been tambouring? couldn't you have been tambouring? couldn't he have been tambouring? couldn't we have been tambouring? couldn't you have been tambouring? couldn't they have been tambouring?