I can invent you can invent he can invent we can invent you can invent they can invent
V-ing form
I can be inventing you can be inventing he can be inventing we can be inventing you can be inventing they can be inventing
Perfect
I can have invented you can have invented he can have invented we can have invented you can have invented they can have invented
V-ing perfect
I can have been inventing you can have been inventing he can have been inventing we can have been inventing you can have been inventing they can have been inventing
Negation
Simple form
I cannot invent you cannot invent he cannot invent we cannot invent you cannot invent they cannot invent
V-ing form
I cannot be inventing you cannot be inventing he cannot be inventing we cannot be inventing you cannot be inventing they cannot be inventing
Perfect
I cannot have invented you cannot have invented he cannot have invented we cannot have invented you cannot have invented they cannot have invented
V-ing perfect
I cannot have been inventing you cannot have been inventing he cannot have been inventing we cannot have been inventing you cannot have been inventing they cannot have been inventing
Interrogative form
Simple form
can I invent? can you invent? can he invent? can we invent? can you invent? can they invent?
V-ing form
can I be inventing? can you be inventing? can he be inventing? can we be inventing? can you be inventing? can they be inventing?
Perfect
can I have invented? can you have invented? can he have invented? can we have invented? can you have invented? can they have invented?
V-ing perfect
can I have been inventing? can you have been inventing? can he have been inventing? can we have been inventing? can you have been inventing? can they have been inventing?
Interro-negative form
Simple form
can I not invent? can you not invent? can he not invent? can we not invent? can you not invent? can they not invent?
V-ing form
can I not be inventing? can you not be inventing? can he not be inventing? can we not be inventing? can you not be inventing? can they not be inventing?
Perfect
can I not have invented? can you not have invented? can he not have invented? can we not have invented? can you not have invented? can they not have invented?
V-ing perfect
can I not have been inventing? can you not have been inventing? can he not have been inventing? can we not have been inventing? can you not have been inventing? can they not have been inventing?