I could schematise you could schematise he could schematise we could schematise you could schematise they could schematise
V-ing form
I could be schematising you could be schematising he could be schematising we could be schematising you could be schematising they could be schematising
Perfect
I could have schematised you could have schematised he could have schematised we could have schematised you could have schematised they could have schematised
V-ing perfect
I could have been schematising you could have been schematising he could have been schematising we could have been schematising you could have been schematising they could have been schematising
Negation
Simple form
I couldn't schematise you couldn't schematise he couldn't schematise we couldn't schematise you couldn't schematise they couldn't schematise
V-ing form
I couldn't be schematising you couldn't be schematising he couldn't be schematising we couldn't be schematising you couldn't be schematising they couldn't be schematising
Perfect
I couldn't have schematised you couldn't have schematised he couldn't have schematised we couldn't have schematised you couldn't have schematised they couldn't have schematised
V-ing perfect
I couldn't have been schematising you couldn't have been schematising he couldn't have been schematising we couldn't have been schematising you couldn't have been schematising they couldn't have been schematising
Interrogative form
Simple form
could I schematise? could you schematise? could he schematise? could we schematise? could you schematise? could they schematise?
V-ing form
could I be schematising? could you be schematising? could he be schematising? could we be schematising? could you be schematising? could they be schematising?
Perfect
could I have schematised? could you have schematised? could he have schematised? could we have schematised? could you have schematised? could they have schematised?
V-ing perfect
could I have been schematising? could you have been schematising? could he have been schematising? could we have been schematising? could you have been schematising? could they have been schematising?
Interro-negative form
Simple form
couldn't I schematise? couldn't you schematise? couldn't he schematise? couldn't we schematise? couldn't you schematise? couldn't they schematise?
V-ing form
couldn't I be schematising? couldn't you be schematising? couldn't he be schematising? couldn't we be schematising? couldn't you be schematising? couldn't they be schematising?
Perfect
couldn't I have schematised? couldn't you have schematised? couldn't he have schematised? couldn't we have schematised? couldn't you have schematised? couldn't they have schematised?
V-ing perfect
couldn't I have been schematising? couldn't you have been schematising? couldn't he have been schematising? couldn't we have been schematising? couldn't you have been schematising? couldn't they have been schematising?