I can extemporize you can extemporize he can extemporize we can extemporize you can extemporize they can extemporize
V-ing form
I can be extemporizing you can be extemporizing he can be extemporizing we can be extemporizing you can be extemporizing they can be extemporizing
Perfect
I can have extemporized you can have extemporized he can have extemporized we can have extemporized you can have extemporized they can have extemporized
V-ing perfect
I can have been extemporizing you can have been extemporizing he can have been extemporizing we can have been extemporizing you can have been extemporizing they can have been extemporizing
Negation
Simple form
I can't extemporize you can't extemporize he can't extemporize we can't extemporize you can't extemporize they can't extemporize
V-ing form
I can't be extemporizing you can't be extemporizing he can't be extemporizing we can't be extemporizing you can't be extemporizing they can't be extemporizing
Perfect
I can't have extemporized you can't have extemporized he can't have extemporized we can't have extemporized you can't have extemporized they can't have extemporized
V-ing perfect
I can't have been extemporizing you can't have been extemporizing he can't have been extemporizing we can't have been extemporizing you can't have been extemporizing they can't have been extemporizing
Interrogative form
Simple form
can I extemporize? can you extemporize? can he extemporize? can we extemporize? can you extemporize? can they extemporize?
V-ing form
can I be extemporizing? can you be extemporizing? can he be extemporizing? can we be extemporizing? can you be extemporizing? can they be extemporizing?
Perfect
can I have extemporized? can you have extemporized? can he have extemporized? can we have extemporized? can you have extemporized? can they have extemporized?
V-ing perfect
can I have been extemporizing? can you have been extemporizing? can he have been extemporizing? can we have been extemporizing? can you have been extemporizing? can they have been extemporizing?
Interro-negative form
Simple form
can't I extemporize? can't you extemporize? can't he extemporize? can't we extemporize? can't you extemporize? can't they extemporize?
V-ing form
can't I be extemporizing? can't you be extemporizing? can't he be extemporizing? can't we be extemporizing? can't you be extemporizing? can't they be extemporizing?
Perfect
can't I have extemporized? can't you have extemporized? can't he have extemporized? can't we have extemporized? can't you have extemporized? can't they have extemporized?
V-ing perfect
can't I have been extemporizing? can't you have been extemporizing? can't he have been extemporizing? can't we have been extemporizing? can't you have been extemporizing? can't they have been extemporizing?