I can tinker you can tinker he can tinker we can tinker you can tinker they can tinker
V-ing form
I can be tinkering you can be tinkering he can be tinkering we can be tinkering you can be tinkering they can be tinkering
Perfect
I can have tinkered you can have tinkered he can have tinkered we can have tinkered you can have tinkered they can have tinkered
V-ing perfect
I can have been tinkering you can have been tinkering he can have been tinkering we can have been tinkering you can have been tinkering they can have been tinkering
Negation
Simple form
I can't tinker you can't tinker he can't tinker we can't tinker you can't tinker they can't tinker
V-ing form
I can't be tinkering you can't be tinkering he can't be tinkering we can't be tinkering you can't be tinkering they can't be tinkering
Perfect
I can't have tinkered you can't have tinkered he can't have tinkered we can't have tinkered you can't have tinkered they can't have tinkered
V-ing perfect
I can't have been tinkering you can't have been tinkering he can't have been tinkering we can't have been tinkering you can't have been tinkering they can't have been tinkering
Interrogative form
Simple form
can I tinker? can you tinker? can he tinker? can we tinker? can you tinker? can they tinker?
V-ing form
can I be tinkering? can you be tinkering? can he be tinkering? can we be tinkering? can you be tinkering? can they be tinkering?
Perfect
can I have tinkered? can you have tinkered? can he have tinkered? can we have tinkered? can you have tinkered? can they have tinkered?
V-ing perfect
can I have been tinkering? can you have been tinkering? can he have been tinkering? can we have been tinkering? can you have been tinkering? can they have been tinkering?
Interro-negative form
Simple form
can't I tinker? can't you tinker? can't he tinker? can't we tinker? can't you tinker? can't they tinker?
V-ing form
can't I be tinkering? can't you be tinkering? can't he be tinkering? can't we be tinkering? can't you be tinkering? can't they be tinkering?
Perfect
can't I have tinkered? can't you have tinkered? can't he have tinkered? can't we have tinkered? can't you have tinkered? can't they have tinkered?
V-ing perfect
can't I have been tinkering? can't you have been tinkering? can't he have been tinkering? can't we have been tinkering? can't you have been tinkering? can't they have been tinkering?