Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could staking you could staking he could staking we could staking you could staking they could staking
V-ing form
I could be stakinging you could be stakinging he could be stakinging we could be stakinging you could be stakinging they could be stakinging
Perfect
I could have stakinged you could have stakinged he could have stakinged we could have stakinged you could have stakinged they could have stakinged
V-ing perfect
I could have been stakinging you could have been stakinging he could have been stakinging we could have been stakinging you could have been stakinging they could have been stakinging
Negation
Simple form
I couldn't staking you couldn't staking he couldn't staking we couldn't staking you couldn't staking they couldn't staking
V-ing form
I couldn't be stakinging you couldn't be stakinging he couldn't be stakinging we couldn't be stakinging you couldn't be stakinging they couldn't be stakinging
Perfect
I couldn't have stakinged you couldn't have stakinged he couldn't have stakinged we couldn't have stakinged you couldn't have stakinged they couldn't have stakinged
V-ing perfect
I couldn't have been stakinging you couldn't have been stakinging he couldn't have been stakinging we couldn't have been stakinging you couldn't have been stakinging they couldn't have been stakinging
Interrogative form
Simple form
could I staking? could you staking? could he staking? could we staking? could you staking? could they staking?
V-ing form
could I be stakinging? could you be stakinging? could he be stakinging? could we be stakinging? could you be stakinging? could they be stakinging?
Perfect
could I have stakinged? could you have stakinged? could he have stakinged? could we have stakinged? could you have stakinged? could they have stakinged?
V-ing perfect
could I have been stakinging? could you have been stakinging? could he have been stakinging? could we have been stakinging? could you have been stakinging? could they have been stakinging?
Interro-negative form
Simple form
couldn't I staking? couldn't you staking? couldn't he staking? couldn't we staking? couldn't you staking? couldn't they staking?
V-ing form
couldn't I be stakinging? couldn't you be stakinging? couldn't he be stakinging? couldn't we be stakinging? couldn't you be stakinging? couldn't they be stakinging?
Perfect
couldn't I have stakinged? couldn't you have stakinged? couldn't he have stakinged? couldn't we have stakinged? couldn't you have stakinged? couldn't they have stakinged?
V-ing perfect
couldn't I have been stakinging? couldn't you have been stakinging? couldn't he have been stakinging? couldn't we have been stakinging? couldn't you have been stakinging? couldn't they have been stakinging?