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