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