I can found you can found he can found we can found you can found they can found
V-ing form
I can be founding you can be founding he can be founding we can be founding you can be founding they can be founding
Perfect
I can have founded you can have founded he can have founded we can have founded you can have founded they can have founded
V-ing perfect
I can have been founding you can have been founding he can have been founding we can have been founding you can have been founding they can have been founding
Negation
Simple form
I can't found you can't found he can't found we can't found you can't found they can't found
V-ing form
I can't be founding you can't be founding he can't be founding we can't be founding you can't be founding they can't be founding
Perfect
I can't have founded you can't have founded he can't have founded we can't have founded you can't have founded they can't have founded
V-ing perfect
I can't have been founding you can't have been founding he can't have been founding we can't have been founding you can't have been founding they can't have been founding
Interrogative form
Simple form
can I found? can you found? can he found? can we found? can you found? can they found?
V-ing form
can I be founding? can you be founding? can he be founding? can we be founding? can you be founding? can they be founding?
Perfect
can I have founded? can you have founded? can he have founded? can we have founded? can you have founded? can they have founded?
V-ing perfect
can I have been founding? can you have been founding? can he have been founding? can we have been founding? can you have been founding? can they have been founding?
Interro-negative form
Simple form
can't I found? can't you found? can't he found? can't we found? can't you found? can't they found?
V-ing form
can't I be founding? can't you be founding? can't he be founding? can't we be founding? can't you be founding? can't they be founding?
Perfect
can't I have founded? can't you have founded? can't he have founded? can't we have founded? can't you have founded? can't they have founded?
V-ing perfect
can't I have been founding? can't you have been founding? can't he have been founding? can't we have been founding? can't you have been founding? can't they have been founding?