could comment
Regular verb: comment - commented- commented

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could comment
you could comment
he could comment
we could comment
you could comment
they could comment 	I could be commenting
you could be commenting
he could be commenting
we could be commenting
you could be commenting
they could be commenting	I could have commented
you could have commented
he could have commented
we could have commented
you could have commented
they could have commented	I could have been commenting
you could have been commenting
he could have been commenting
we could have been commenting
you could have been commenting
they could have been commenting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't comment
you couldn't comment
he couldn't comment
we couldn't comment
you couldn't comment
they couldn't comment 	I couldn't be commenting
you couldn't be commenting
he couldn't be commenting
we couldn't be commenting
you couldn't be commenting
they couldn't be commenting	I couldn't have commented
you couldn't have commented
he couldn't have commented
we couldn't have commented
you couldn't have commented
they couldn't have commented	I couldn't have been commenting
you couldn't have been commenting
he couldn't have been commenting
we couldn't have been commenting
you couldn't have been commenting
they couldn't have been commenting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I comment?
could you comment?
could he comment?
could we comment?
could you comment?
could they comment? 	could I be commenting?
could you be commenting?
could he be commenting?
could we be commenting?
could you be commenting?
could they be commenting? 	could I have commented?
could you have commented?
could he have commented?
could we have commented?
could you have commented?
could they have commented? 	could I have been commenting?
could you have been commenting?
could he have been commenting?
could we have been commenting?
could you have been commenting?
could they have been commenting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I comment?
couldn't you comment?
couldn't he comment?
couldn't we comment?
couldn't you comment?
couldn't they comment? 	couldn't I be commenting?
couldn't you be commenting?
couldn't he be commenting?
couldn't we be commenting?
couldn't you be commenting?
couldn't they be commenting? 	couldn't I have commented?
couldn't you have commented?
couldn't he have commented?
couldn't we have commented?
couldn't you have commented?
couldn't they have commented? 	couldn't I have been commenting?
couldn't you have been commenting?
couldn't he have been commenting?
couldn't we have been commenting?
couldn't you have been commenting?
couldn't they have been commenting?