I can discard you can discard he can discard we can discard you can discard they can discard
V-ing form
I can be discarding you can be discarding he can be discarding we can be discarding you can be discarding they can be discarding
Perfect
I can have discarded you can have discarded he can have discarded we can have discarded you can have discarded they can have discarded
V-ing perfect
I can have been discarding you can have been discarding he can have been discarding we can have been discarding you can have been discarding they can have been discarding
Negation
Simple form
I can't discard you can't discard he can't discard we can't discard you can't discard they can't discard
V-ing form
I can't be discarding you can't be discarding he can't be discarding we can't be discarding you can't be discarding they can't be discarding
Perfect
I can't have discarded you can't have discarded he can't have discarded we can't have discarded you can't have discarded they can't have discarded
V-ing perfect
I can't have been discarding you can't have been discarding he can't have been discarding we can't have been discarding you can't have been discarding they can't have been discarding
Interrogative form
Simple form
can I discard? can you discard? can he discard? can we discard? can you discard? can they discard?
V-ing form
can I be discarding? can you be discarding? can he be discarding? can we be discarding? can you be discarding? can they be discarding?
Perfect
can I have discarded? can you have discarded? can he have discarded? can we have discarded? can you have discarded? can they have discarded?
V-ing perfect
can I have been discarding? can you have been discarding? can he have been discarding? can we have been discarding? can you have been discarding? can they have been discarding?
Interro-negative form
Simple form
can't I discard? can't you discard? can't he discard? can't we discard? can't you discard? can't they discard?
V-ing form
can't I be discarding? can't you be discarding? can't he be discarding? can't we be discarding? can't you be discarding? can't they be discarding?
Perfect
can't I have discarded? can't you have discarded? can't he have discarded? can't we have discarded? can't you have discarded? can't they have discarded?
V-ing perfect
can't I have been discarding? can't you have been discarding? can't he have been discarding? can't we have been discarding? can't you have been discarding? can't they have been discarding?