could tube
Verbe régulier : tube - tubed- tubed

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could tube
you could tube
he could tube
we could tube
you could tube
they could tube 	I could be tubing
you could be tubing
he could be tubing
we could be tubing
you could be tubing
they could be tubing	I could have tubed
you could have tubed
he could have tubed
we could have tubed
you could have tubed
they could have tubed	I could have been tubing
you could have been tubing
he could have been tubing
we could have been tubing
you could have been tubing
they could have been tubing	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I couldn't tube
you couldn't tube
he couldn't tube
we couldn't tube
you couldn't tube
they couldn't tube 	I couldn't be tubing
you couldn't be tubing
he couldn't be tubing
we couldn't be tubing
you couldn't be tubing
they couldn't be tubing	I couldn't have tubed
you couldn't have tubed
he couldn't have tubed
we couldn't have tubed
you couldn't have tubed
they couldn't have tubed	I couldn't have been tubing
you couldn't have been tubing
he couldn't have been tubing
we couldn't have been tubing
you couldn't have been tubing
they couldn't have been tubing	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I tube?
could you tube?
could he tube?
could we tube?
could you tube?
could they tube? 	could I be tubing?
could you be tubing?
could he be tubing?
could we be tubing?
could you be tubing?
could they be tubing? 	could I have tubed?
could you have tubed?
could he have tubed?
could we have tubed?
could you have tubed?
could they have tubed? 	could I have been tubing?
could you have been tubing?
could he have been tubing?
could we have been tubing?
could you have been tubing?
could they have been tubing? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
couldn't I tube?
couldn't you tube?
couldn't he tube?
couldn't we tube?
couldn't you tube?
couldn't they tube? 	couldn't I be tubing?
couldn't you be tubing?
couldn't he be tubing?
couldn't we be tubing?
couldn't you be tubing?
couldn't they be tubing? 	couldn't I have tubed?
couldn't you have tubed?
couldn't he have tubed?
couldn't we have tubed?
couldn't you have tubed?
couldn't they have tubed? 	couldn't I have been tubing?
couldn't you have been tubing?
couldn't he have been tubing?
couldn't we have been tubing?
couldn't you have been tubing?
couldn't they have been tubing?