should discolour
Regular verb: discolour - discoloured- discoloured

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I'd discolour
you'd discolour
he'd discolour
we'd discolour
you'd discolour
they'd discolour 	I'd be discolouring
you'd be discolouring
he'd be discolouring
we'd be discolouring
you'd be discolouring
they'd be discolouring	I should've discoloured
you should've discoloured
he should've discoloured
we should've discoloured
you should've discoloured
they should've discoloured	I should've been discolouring
you should've been discolouring
he should've been discolouring
we should've been discolouring
you should've been discolouring
they should've been discolouring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I shouldn't discolour
you shouldn't discolour
he shouldn't discolour
we shouldn't discolour
you shouldn't discolour
they shouldn't discolour 	I shouldn't be discolouring
you shouldn't be discolouring
he shouldn't be discolouring
we shouldn't be discolouring
you shouldn't be discolouring
they shouldn't be discolouring	I shouldn't have discoloured
you shouldn't have discoloured
he shouldn't have discoloured
we shouldn't have discoloured
you shouldn't have discoloured
they shouldn't have discoloured	I shouldn't have been discolouring
you shouldn't have been discolouring
he shouldn't have been discolouring
we shouldn't have been discolouring
you shouldn't have been discolouring
they shouldn't have been discolouring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I discolour?
should you discolour?
should he discolour?
should we discolour?
should you discolour?
should they discolour? 	should I be discolouring?
should you be discolouring?
should he be discolouring?
should we be discolouring?
should you be discolouring?
should they be discolouring? 	should I have discoloured?
should you have discoloured?
should he have discoloured?
should we have discoloured?
should you have discoloured?
should they have discoloured? 	should I have been discolouring?
should you have been discolouring?
should he have been discolouring?
should we have been discolouring?
should you have been discolouring?
should they have been discolouring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
shouldn't I discolour?
shouldn't you discolour?
shouldn't he discolour?
shouldn't we discolour?
shouldn't you discolour?
shouldn't they discolour? 	shouldn't I be discolouring?
shouldn't you be discolouring?
shouldn't he be discolouring?
shouldn't we be discolouring?
shouldn't you be discolouring?
shouldn't they be discolouring? 	shouldn't I have discoloured?
shouldn't you have discoloured?
shouldn't he have discoloured?
shouldn't we have discoloured?
shouldn't you have discoloured?
shouldn't they have discoloured? 	shouldn't I have been discolouring?
shouldn't you have been discolouring?
shouldn't he have been discolouring?
shouldn't we have been discolouring?
shouldn't you have been discolouring?
shouldn't they have been discolouring?