I can question you can question he can question we can question you can question they can question
V-ing form
I can be questioning you can be questioning he can be questioning we can be questioning you can be questioning they can be questioning
Perfect
I can have questioned you can have questioned he can have questioned we can have questioned you can have questioned they can have questioned
V-ing perfect
I can have been questioning you can have been questioning he can have been questioning we can have been questioning you can have been questioning they can have been questioning
Negation
Simple form
I can't question you can't question he can't question we can't question you can't question they can't question
V-ing form
I can't be questioning you can't be questioning he can't be questioning we can't be questioning you can't be questioning they can't be questioning
Perfect
I can't have questioned you can't have questioned he can't have questioned we can't have questioned you can't have questioned they can't have questioned
V-ing perfect
I can't have been questioning you can't have been questioning he can't have been questioning we can't have been questioning you can't have been questioning they can't have been questioning
Interrogative form
Simple form
can I question? can you question? can he question? can we question? can you question? can they question?
V-ing form
can I be questioning? can you be questioning? can he be questioning? can we be questioning? can you be questioning? can they be questioning?
Perfect
can I have questioned? can you have questioned? can he have questioned? can we have questioned? can you have questioned? can they have questioned?
V-ing perfect
can I have been questioning? can you have been questioning? can he have been questioning? can we have been questioning? can you have been questioning? can they have been questioning?
Interro-negative form
Simple form
can't I question? can't you question? can't he question? can't we question? can't you question? can't they question?
V-ing form
can't I be questioning? can't you be questioning? can't he be questioning? can't we be questioning? can't you be questioning? can't they be questioning?
Perfect
can't I have questioned? can't you have questioned? can't he have questioned? can't we have questioned? can't you have questioned? can't they have questioned?
V-ing perfect
can't I have been questioning? can't you have been questioning? can't he have been questioning? can't we have been questioning? can't you have been questioning? can't they have been questioning?