I can specialize you can specialize he can specialize we can specialize you can specialize they can specialize
V-ing form
I can be specializing you can be specializing he can be specializing we can be specializing you can be specializing they can be specializing
Perfect
I can have specialized you can have specialized he can have specialized we can have specialized you can have specialized they can have specialized
V-ing perfect
I can have been specializing you can have been specializing he can have been specializing we can have been specializing you can have been specializing they can have been specializing
Negation
Simple form
I can't specialize you can't specialize he can't specialize we can't specialize you can't specialize they can't specialize
V-ing form
I can't be specializing you can't be specializing he can't be specializing we can't be specializing you can't be specializing they can't be specializing
Perfect
I can't have specialized you can't have specialized he can't have specialized we can't have specialized you can't have specialized they can't have specialized
V-ing perfect
I can't have been specializing you can't have been specializing he can't have been specializing we can't have been specializing you can't have been specializing they can't have been specializing
Interrogative form
Simple form
can I specialize? can you specialize? can he specialize? can we specialize? can you specialize? can they specialize?
V-ing form
can I be specializing? can you be specializing? can he be specializing? can we be specializing? can you be specializing? can they be specializing?
Perfect
can I have specialized? can you have specialized? can he have specialized? can we have specialized? can you have specialized? can they have specialized?
V-ing perfect
can I have been specializing? can you have been specializing? can he have been specializing? can we have been specializing? can you have been specializing? can they have been specializing?
Interro-negative form
Simple form
can't I specialize? can't you specialize? can't he specialize? can't we specialize? can't you specialize? can't they specialize?
V-ing form
can't I be specializing? can't you be specializing? can't he be specializing? can't we be specializing? can't you be specializing? can't they be specializing?
Perfect
can't I have specialized? can't you have specialized? can't he have specialized? can't we have specialized? can't you have specialized? can't they have specialized?
V-ing perfect
can't I have been specializing? can't you have been specializing? can't he have been specializing? can't we have been specializing? can't you have been specializing? can't they have been specializing?