could assemble
Regular verb: assemble - assembled- assembled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could assemble
you could assemble
he could assemble
we could assemble
you could assemble
they could assemble 	I could be assembling
you could be assembling
he could be assembling
we could be assembling
you could be assembling
they could be assembling	I could have assembled
you could have assembled
he could have assembled
we could have assembled
you could have assembled
they could have assembled	I could have been assembling
you could have been assembling
he could have been assembling
we could have been assembling
you could have been assembling
they could have been assembling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't assemble
you couldn't assemble
he couldn't assemble
we couldn't assemble
you couldn't assemble
they couldn't assemble 	I couldn't be assembling
you couldn't be assembling
he couldn't be assembling
we couldn't be assembling
you couldn't be assembling
they couldn't be assembling	I couldn't have assembled
you couldn't have assembled
he couldn't have assembled
we couldn't have assembled
you couldn't have assembled
they couldn't have assembled	I couldn't have been assembling
you couldn't have been assembling
he couldn't have been assembling
we couldn't have been assembling
you couldn't have been assembling
they couldn't have been assembling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I assemble?
could you assemble?
could he assemble?
could we assemble?
could you assemble?
could they assemble? 	could I be assembling?
could you be assembling?
could he be assembling?
could we be assembling?
could you be assembling?
could they be assembling? 	could I have assembled?
could you have assembled?
could he have assembled?
could we have assembled?
could you have assembled?
could they have assembled? 	could I have been assembling?
could you have been assembling?
could he have been assembling?
could we have been assembling?
could you have been assembling?
could they have been assembling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I assemble?
couldn't you assemble?
couldn't he assemble?
couldn't we assemble?
couldn't you assemble?
couldn't they assemble? 	couldn't I be assembling?
couldn't you be assembling?
couldn't he be assembling?
couldn't we be assembling?
couldn't you be assembling?
couldn't they be assembling? 	couldn't I have assembled?
couldn't you have assembled?
couldn't he have assembled?
couldn't we have assembled?
couldn't you have assembled?
couldn't they have assembled? 	couldn't I have been assembling?
couldn't you have been assembling?
couldn't he have been assembling?
couldn't we have been assembling?
couldn't you have been assembling?
couldn't they have been assembling?