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