English verb conjugation
CAN QUESTION

Regular verb: question - questioned - questioned

Affirmation

Simple form	V-ing form
I can question you can question he can question we can question you can question they can question	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	V-ing 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	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	V-ing 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	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	V-ing 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	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	V-ing form
can I question? can you question? can he question? can we question? can you question? can they question?	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	V-ing 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?	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	V-ing 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?	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	V-ing 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?	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?