I could fine-tune you could fine-tune he could fine-tune we could fine-tune you could fine-tune they could fine-tune
V-ing form
I could be fine-tuning you could be fine-tuning he could be fine-tuning we could be fine-tuning you could be fine-tuning they could be fine-tuning
Perfect
I could have fine-tuned you could have fine-tuned he could have fine-tuned we could have fine-tuned you could have fine-tuned they could have fine-tuned
V-ing perfect
I could have been fine-tuning you could have been fine-tuning he could have been fine-tuning we could have been fine-tuning you could have been fine-tuning they could have been fine-tuning
Negation
Simple form
I couldn't fine-tune you couldn't fine-tune he couldn't fine-tune we couldn't fine-tune you couldn't fine-tune they couldn't fine-tune
V-ing form
I couldn't be fine-tuning you couldn't be fine-tuning he couldn't be fine-tuning we couldn't be fine-tuning you couldn't be fine-tuning they couldn't be fine-tuning
Perfect
I couldn't have fine-tuned you couldn't have fine-tuned he couldn't have fine-tuned we couldn't have fine-tuned you couldn't have fine-tuned they couldn't have fine-tuned
V-ing perfect
I couldn't have been fine-tuning you couldn't have been fine-tuning he couldn't have been fine-tuning we couldn't have been fine-tuning you couldn't have been fine-tuning they couldn't have been fine-tuning
Interrogative form
Simple form
could I fine-tune? could you fine-tune? could he fine-tune? could we fine-tune? could you fine-tune? could they fine-tune?
V-ing form
could I be fine-tuning? could you be fine-tuning? could he be fine-tuning? could we be fine-tuning? could you be fine-tuning? could they be fine-tuning?
Perfect
could I have fine-tuned? could you have fine-tuned? could he have fine-tuned? could we have fine-tuned? could you have fine-tuned? could they have fine-tuned?
V-ing perfect
could I have been fine-tuning? could you have been fine-tuning? could he have been fine-tuning? could we have been fine-tuning? could you have been fine-tuning? could they have been fine-tuning?
Interro-negative form
Simple form
couldn't I fine-tune? couldn't you fine-tune? couldn't he fine-tune? couldn't we fine-tune? couldn't you fine-tune? couldn't they fine-tune?
V-ing form
couldn't I be fine-tuning? couldn't you be fine-tuning? couldn't he be fine-tuning? couldn't we be fine-tuning? couldn't you be fine-tuning? couldn't they be fine-tuning?
Perfect
couldn't I have fine-tuned? couldn't you have fine-tuned? couldn't he have fine-tuned? couldn't we have fine-tuned? couldn't you have fine-tuned? couldn't they have fine-tuned?
V-ing perfect
couldn't I have been fine-tuning? couldn't you have been fine-tuning? couldn't he have been fine-tuning? couldn't we have been fine-tuning? couldn't you have been fine-tuning? couldn't they have been fine-tuning?