English verb conjugation
COULD PRACTICE

Regular verb: practice - practiced - practiced

Affirmation

Simple form	V-ing form
I could practice you could practice he could practice we could practice you could practice they could practice	I could be practicing you could be practicing he could be practicing we could be practicing you could be practicing they could be practicing
Perfect	V-ing perfect
I could have practiced you could have practiced he could have practiced we could have practiced you could have practiced they could have practiced	I could have been practicing you could have been practicing he could have been practicing we could have been practicing you could have been practicing they could have been practicing

Negation

Simple form	V-ing form
I couldn't practice you couldn't practice he couldn't practice we couldn't practice you couldn't practice they couldn't practice	I couldn't be practicing you couldn't be practicing he couldn't be practicing we couldn't be practicing you couldn't be practicing they couldn't be practicing
Perfect	V-ing perfect
I couldn't have practiced you couldn't have practiced he couldn't have practiced we couldn't have practiced you couldn't have practiced they couldn't have practiced	I couldn't have been practicing you couldn't have been practicing he couldn't have been practicing we couldn't have been practicing you couldn't have been practicing they couldn't have been practicing

Interrogative form

Simple form	V-ing form
could I practice? could you practice? could he practice? could we practice? could you practice? could they practice?	could I be practicing? could you be practicing? could he be practicing? could we be practicing? could you be practicing? could they be practicing?
Perfect	V-ing perfect
could I have practiced? could you have practiced? could he have practiced? could we have practiced? could you have practiced? could they have practiced?	could I have been practicing? could you have been practicing? could he have been practicing? could we have been practicing? could you have been practicing? could they have been practicing?

Interro-negative form

Simple form	V-ing form
couldn't I practice? couldn't you practice? couldn't he practice? couldn't we practice? couldn't you practice? couldn't they practice?	couldn't I be practicing? couldn't you be practicing? couldn't he be practicing? couldn't we be practicing? couldn't you be practicing? couldn't they be practicing?
Perfect	V-ing perfect
couldn't I have practiced? couldn't you have practiced? couldn't he have practiced? couldn't we have practiced? couldn't you have practiced? couldn't they have practiced?	couldn't I have been practicing? couldn't you have been practicing? couldn't he have been practicing? couldn't we have been practicing? couldn't you have been practicing? couldn't they have been practicing?