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