I can falsify you can falsify he can falsify we can falsify you can falsify they can falsify
V-ing form
I can be falsifying you can be falsifying he can be falsifying we can be falsifying you can be falsifying they can be falsifying
Perfect
I can have falsified you can have falsified he can have falsified we can have falsified you can have falsified they can have falsified
V-ing perfect
I can have been falsifying you can have been falsifying he can have been falsifying we can have been falsifying you can have been falsifying they can have been falsifying
Negation
Simple form
I can't falsify you can't falsify he can't falsify we can't falsify you can't falsify they can't falsify
V-ing form
I can't be falsifying you can't be falsifying he can't be falsifying we can't be falsifying you can't be falsifying they can't be falsifying
Perfect
I can't have falsified you can't have falsified he can't have falsified we can't have falsified you can't have falsified they can't have falsified
V-ing perfect
I can't have been falsifying you can't have been falsifying he can't have been falsifying we can't have been falsifying you can't have been falsifying they can't have been falsifying
Interrogative form
Simple form
can I falsify? can you falsify? can he falsify? can we falsify? can you falsify? can they falsify?
V-ing form
can I be falsifying? can you be falsifying? can he be falsifying? can we be falsifying? can you be falsifying? can they be falsifying?
Perfect
can I have falsified? can you have falsified? can he have falsified? can we have falsified? can you have falsified? can they have falsified?
V-ing perfect
can I have been falsifying? can you have been falsifying? can he have been falsifying? can we have been falsifying? can you have been falsifying? can they have been falsifying?
Interro-negative form
Simple form
can't I falsify? can't you falsify? can't he falsify? can't we falsify? can't you falsify? can't they falsify?
V-ing form
can't I be falsifying? can't you be falsifying? can't he be falsifying? can't we be falsifying? can't you be falsifying? can't they be falsifying?
Perfect
can't I have falsified? can't you have falsified? can't he have falsified? can't we have falsified? can't you have falsified? can't they have falsified?
V-ing perfect
can't I have been falsifying? can't you have been falsifying? can't he have been falsifying? can't we have been falsifying? can't you have been falsifying? can't they have been falsifying?