English verb conjugation
COULD ITCH

Regular verb: itch - itched - itched

Affirmation

Simple form	V-ing form
I could itch you could itch he could itch we could itch you could itch they could itch	I could be itching you could be itching he could be itching we could be itching you could be itching they could be itching
Perfect	V-ing perfect
I could have itched you could have itched he could have itched we could have itched you could have itched they could have itched	I could have been itching you could have been itching he could have been itching we could have been itching you could have been itching they could have been itching

Negation

Simple form	V-ing form
I couldn't itch you couldn't itch he couldn't itch we couldn't itch you couldn't itch they couldn't itch	I couldn't be itching you couldn't be itching he couldn't be itching we couldn't be itching you couldn't be itching they couldn't be itching
Perfect	V-ing perfect
I couldn't have itched you couldn't have itched he couldn't have itched we couldn't have itched you couldn't have itched they couldn't have itched	I couldn't have been itching you couldn't have been itching he couldn't have been itching we couldn't have been itching you couldn't have been itching they couldn't have been itching

Interrogative form

Simple form	V-ing form
could I itch? could you itch? could he itch? could we itch? could you itch? could they itch?	could I be itching? could you be itching? could he be itching? could we be itching? could you be itching? could they be itching?
Perfect	V-ing perfect
could I have itched? could you have itched? could he have itched? could we have itched? could you have itched? could they have itched?	could I have been itching? could you have been itching? could he have been itching? could we have been itching? could you have been itching? could they have been itching?

Interro-negative form

Simple form	V-ing form
couldn't I itch? couldn't you itch? couldn't he itch? couldn't we itch? couldn't you itch? couldn't they itch?	couldn't I be itching? couldn't you be itching? couldn't he be itching? couldn't we be itching? couldn't you be itching? couldn't they be itching?
Perfect	V-ing perfect
couldn't I have itched? couldn't you have itched? couldn't he have itched? couldn't we have itched? couldn't you have itched? couldn't they have itched?	couldn't I have been itching? couldn't you have been itching? couldn't he have been itching? couldn't we have been itching? couldn't you have been itching? couldn't they have been itching?