I can collect you can collect he can collect we can collect you can collect they can collect
V-ing form
I can be collecting you can be collecting he can be collecting we can be collecting you can be collecting they can be collecting
Perfect
I can have collected you can have collected he can have collected we can have collected you can have collected they can have collected
V-ing perfect
I can have been collecting you can have been collecting he can have been collecting we can have been collecting you can have been collecting they can have been collecting
Negation
Simple form
I cannot collect you cannot collect he cannot collect we cannot collect you cannot collect they cannot collect
V-ing form
I cannot be collecting you cannot be collecting he cannot be collecting we cannot be collecting you cannot be collecting they cannot be collecting
Perfect
I cannot have collected you cannot have collected he cannot have collected we cannot have collected you cannot have collected they cannot have collected
V-ing perfect
I cannot have been collecting you cannot have been collecting he cannot have been collecting we cannot have been collecting you cannot have been collecting they cannot have been collecting
Interrogative form
Simple form
can I collect? can you collect? can he collect? can we collect? can you collect? can they collect?
V-ing form
can I be collecting? can you be collecting? can he be collecting? can we be collecting? can you be collecting? can they be collecting?
Perfect
can I have collected? can you have collected? can he have collected? can we have collected? can you have collected? can they have collected?
V-ing perfect
can I have been collecting? can you have been collecting? can he have been collecting? can we have been collecting? can you have been collecting? can they have been collecting?
Interro-negative form
Simple form
can I not collect? can you not collect? can he not collect? can we not collect? can you not collect? can they not collect?
V-ing form
can I not be collecting? can you not be collecting? can he not be collecting? can we not be collecting? can you not be collecting? can they not be collecting?
Perfect
can I not have collected? can you not have collected? can he not have collected? can we not have collected? can you not have collected? can they not have collected?
V-ing perfect
can I not have been collecting? can you not have been collecting? can he not have been collecting? can we not have been collecting? can you not have been collecting? can they not have been collecting?