I can taper you can taper he can taper we can taper you can taper they can taper
V-ing form
I can be tapering you can be tapering he can be tapering we can be tapering you can be tapering they can be tapering
Perfect
I can have tapered you can have tapered he can have tapered we can have tapered you can have tapered they can have tapered
V-ing perfect
I can have been tapering you can have been tapering he can have been tapering we can have been tapering you can have been tapering they can have been tapering
Negation
Simple form
I can't taper you can't taper he can't taper we can't taper you can't taper they can't taper
V-ing form
I can't be tapering you can't be tapering he can't be tapering we can't be tapering you can't be tapering they can't be tapering
Perfect
I can't have tapered you can't have tapered he can't have tapered we can't have tapered you can't have tapered they can't have tapered
V-ing perfect
I can't have been tapering you can't have been tapering he can't have been tapering we can't have been tapering you can't have been tapering they can't have been tapering
Interrogative form
Simple form
can I taper? can you taper? can he taper? can we taper? can you taper? can they taper?
V-ing form
can I be tapering? can you be tapering? can he be tapering? can we be tapering? can you be tapering? can they be tapering?
Perfect
can I have tapered? can you have tapered? can he have tapered? can we have tapered? can you have tapered? can they have tapered?
V-ing perfect
can I have been tapering? can you have been tapering? can he have been tapering? can we have been tapering? can you have been tapering? can they have been tapering?
Interro-negative form
Simple form
can't I taper? can't you taper? can't he taper? can't we taper? can't you taper? can't they taper?
V-ing form
can't I be tapering? can't you be tapering? can't he be tapering? can't we be tapering? can't you be tapering? can't they be tapering?
Perfect
can't I have tapered? can't you have tapered? can't he have tapered? can't we have tapered? can't you have tapered? can't they have tapered?
V-ing perfect
can't I have been tapering? can't you have been tapering? can't he have been tapering? can't we have been tapering? can't you have been tapering? can't they have been tapering?