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