I can try you can try he can try we can try you can try they can try
V-ing form
I can be trying you can be trying he can be trying we can be trying you can be trying they can be trying
Perfect
I can have tried you can have tried he can have tried we can have tried you can have tried they can have tried
V-ing perfect
I can have been trying you can have been trying he can have been trying we can have been trying you can have been trying they can have been trying
Negation
Simple form
I cannot try you cannot try he cannot try we cannot try you cannot try they cannot try
V-ing form
I cannot be trying you cannot be trying he cannot be trying we cannot be trying you cannot be trying they cannot be trying
Perfect
I cannot have tried you cannot have tried he cannot have tried we cannot have tried you cannot have tried they cannot have tried
V-ing perfect
I cannot have been trying you cannot have been trying he cannot have been trying we cannot have been trying you cannot have been trying they cannot have been trying
Interrogative form
Simple form
can I try? can you try? can he try? can we try? can you try? can they try?
V-ing form
can I be trying? can you be trying? can he be trying? can we be trying? can you be trying? can they be trying?
Perfect
can I have tried? can you have tried? can he have tried? can we have tried? can you have tried? can they have tried?
V-ing perfect
can I have been trying? can you have been trying? can he have been trying? can we have been trying? can you have been trying? can they have been trying?
Interro-negative form
Simple form
can I not try? can you not try? can he not try? can we not try? can you not try? can they not try?
V-ing form
can I not be trying? can you not be trying? can he not be trying? can we not be trying? can you not be trying? can they not be trying?
Perfect
can I not have tried? can you not have tried? can he not have tried? can we not have tried? can you not have tried? can they not have tried?
V-ing perfect
can I not have been trying? can you not have been trying? can he not have been trying? can we not have been trying? can you not have been trying? can they not have been trying?