I could assemble you could assemble she could assemble we could assemble you could assemble they could assemble
V-ing form
I could be assembling you could be assembling she could be assembling we could be assembling you could be assembling they could be assembling
Perfect
I could have assembled you could have assembled she could have assembled we could have assembled you could have assembled they could have assembled
V-ing perfect
I could have been assembling you could have been assembling she could have been assembling we could have been assembling you could have been assembling they could have been assembling
Negation
Simple form
I could not assemble you could not assemble she could not assemble we could not assemble you could not assemble they could not assemble
V-ing form
I could not be assembling you could not be assembling she could not be assembling we could not be assembling you could not be assembling they could not be assembling
Perfect
I could not have assembled you could not have assembled she could not have assembled we could not have assembled you could not have assembled they could not have assembled
V-ing perfect
I could not have been assembling you could not have been assembling she could not have been assembling we could not have been assembling you could not have been assembling they could not have been assembling
Interrogative form
Simple form
could I assemble? could you assemble? could she assemble? could we assemble? could you assemble? could they assemble?
V-ing form
could I be assembling? could you be assembling? could she be assembling? could we be assembling? could you be assembling? could they be assembling?
Perfect
could I have assembled? could you have assembled? could she have assembled? could we have assembled? could you have assembled? could they have assembled?
V-ing perfect
could I have been assembling? could you have been assembling? could she have been assembling? could we have been assembling? could you have been assembling? could they have been assembling?
Interro-negative form
Simple form
could I not assemble? could you not assemble? could she not assemble? could we not assemble? could you not assemble? could they not assemble?
V-ing form
could I not be assembling? could you not be assembling? could she not be assembling? could we not be assembling? could you not be assembling? could they not be assembling?
Perfect
could I not have assembled? could you not have assembled? could she not have assembled? could we not have assembled? could you not have assembled? could they not have assembled?
V-ing perfect
could I not have been assembling? could you not have been assembling? could she not have been assembling? could we not have been assembling? could you not have been assembling? could they not have been assembling?