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