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