I could disturb you could disturb she could disturb we could disturb you could disturb they could disturb
V-ing form
I could be disturbing you could be disturbing she could be disturbing we could be disturbing you could be disturbing they could be disturbing
Perfect
I could have disturbed you could have disturbed she could have disturbed we could have disturbed you could have disturbed they could have disturbed
V-ing perfect
I could have been disturbing you could have been disturbing she could have been disturbing we could have been disturbing you could have been disturbing they could have been disturbing
Negation
Simple form
I couldn't disturb you couldn't disturb she couldn't disturb we couldn't disturb you couldn't disturb they couldn't disturb
V-ing form
I couldn't be disturbing you couldn't be disturbing she couldn't be disturbing we couldn't be disturbing you couldn't be disturbing they couldn't be disturbing
Perfect
I couldn't have disturbed you couldn't have disturbed she couldn't have disturbed we couldn't have disturbed you couldn't have disturbed they couldn't have disturbed
V-ing perfect
I couldn't have been disturbing you couldn't have been disturbing she couldn't have been disturbing we couldn't have been disturbing you couldn't have been disturbing they couldn't have been disturbing
Interrogative form
Simple form
could I disturb? could you disturb? could she disturb? could we disturb? could you disturb? could they disturb?
V-ing form
could I be disturbing? could you be disturbing? could she be disturbing? could we be disturbing? could you be disturbing? could they be disturbing?
Perfect
could I have disturbed? could you have disturbed? could she have disturbed? could we have disturbed? could you have disturbed? could they have disturbed?
V-ing perfect
could I have been disturbing? could you have been disturbing? could she have been disturbing? could we have been disturbing? could you have been disturbing? could they have been disturbing?
Interro-negative form
Simple form
couldn't I disturb? couldn't you disturb? couldn't she disturb? couldn't we disturb? couldn't you disturb? couldn't they disturb?
V-ing form
couldn't I be disturbing? couldn't you be disturbing? couldn't she be disturbing? couldn't we be disturbing? couldn't you be disturbing? couldn't they be disturbing?
Perfect
couldn't I have disturbed? couldn't you have disturbed? couldn't she have disturbed? couldn't we have disturbed? couldn't you have disturbed? couldn't they have disturbed?
V-ing perfect
couldn't I have been disturbing? couldn't you have been disturbing? couldn't she have been disturbing? couldn't we have been disturbing? couldn't you have been disturbing? couldn't they have been disturbing?