I can clarify you can clarify he can clarify we can clarify you can clarify they can clarify
V-ing form
I can be clarifying you can be clarifying he can be clarifying we can be clarifying you can be clarifying they can be clarifying
Perfect
I can have clarified you can have clarified he can have clarified we can have clarified you can have clarified they can have clarified
V-ing perfect
I can have been clarifying you can have been clarifying he can have been clarifying we can have been clarifying you can have been clarifying they can have been clarifying
Negation
Simple form
I can't clarify you can't clarify he can't clarify we can't clarify you can't clarify they can't clarify
V-ing form
I can't be clarifying you can't be clarifying he can't be clarifying we can't be clarifying you can't be clarifying they can't be clarifying
Perfect
I can't have clarified you can't have clarified he can't have clarified we can't have clarified you can't have clarified they can't have clarified
V-ing perfect
I can't have been clarifying you can't have been clarifying he can't have been clarifying we can't have been clarifying you can't have been clarifying they can't have been clarifying
Interrogative form
Simple form
can I clarify? can you clarify? can he clarify? can we clarify? can you clarify? can they clarify?
V-ing form
can I be clarifying? can you be clarifying? can he be clarifying? can we be clarifying? can you be clarifying? can they be clarifying?
Perfect
can I have clarified? can you have clarified? can he have clarified? can we have clarified? can you have clarified? can they have clarified?
V-ing perfect
can I have been clarifying? can you have been clarifying? can he have been clarifying? can we have been clarifying? can you have been clarifying? can they have been clarifying?
Interro-negative form
Simple form
can't I clarify? can't you clarify? can't he clarify? can't we clarify? can't you clarify? can't they clarify?
V-ing form
can't I be clarifying? can't you be clarifying? can't he be clarifying? can't we be clarifying? can't you be clarifying? can't they be clarifying?
Perfect
can't I have clarified? can't you have clarified? can't he have clarified? can't we have clarified? can't you have clarified? can't they have clarified?
V-ing perfect
can't I have been clarifying? can't you have been clarifying? can't he have been clarifying? can't we have been clarifying? can't you have been clarifying? can't they have been clarifying?