I can center you can center she can center we can center you can center they can center
V-ing form
I can be centering you can be centering she can be centering we can be centering you can be centering they can be centering
Perfect
I can have centered you can have centered she can have centered we can have centered you can have centered they can have centered
V-ing perfect
I can have been centering you can have been centering she can have been centering we can have been centering you can have been centering they can have been centering
Negation
Simple form
I can't center you can't center she can't center we can't center you can't center they can't center
V-ing form
I can't be centering you can't be centering she can't be centering we can't be centering you can't be centering they can't be centering
Perfect
I can't have centered you can't have centered she can't have centered we can't have centered you can't have centered they can't have centered
V-ing perfect
I can't have been centering you can't have been centering she can't have been centering we can't have been centering you can't have been centering they can't have been centering
Interrogative form
Simple form
can I center? can you center? can she center? can we center? can you center? can they center?
V-ing form
can I be centering? can you be centering? can she be centering? can we be centering? can you be centering? can they be centering?
Perfect
can I have centered? can you have centered? can she have centered? can we have centered? can you have centered? can they have centered?
V-ing perfect
can I have been centering? can you have been centering? can she have been centering? can we have been centering? can you have been centering? can they have been centering?
Interro-negative form
Simple form
can't I center? can't you center? can't she center? can't we center? can't you center? can't they center?
V-ing form
can't I be centering? can't you be centering? can't she be centering? can't we be centering? can't you be centering? can't they be centering?
Perfect
can't I have centered? can't you have centered? can't she have centered? can't we have centered? can't you have centered? can't they have centered?
V-ing perfect
can't I have been centering? can't you have been centering? can't she have been centering? can't we have been centering? can't you have been centering? can't they have been centering?