English verb conjugation
COULD ADJOIN

Regular verb: adjoin - adjoined - adjoined

Affirmation

Simple form	V-ing form
I could adjoin you could adjoin he could adjoin we could adjoin you could adjoin they could adjoin	I could be adjoining you could be adjoining he could be adjoining we could be adjoining you could be adjoining they could be adjoining
Perfect	V-ing perfect
I could have adjoined you could have adjoined he could have adjoined we could have adjoined you could have adjoined they could have adjoined	I could have been adjoining you could have been adjoining he could have been adjoining we could have been adjoining you could have been adjoining they could have been adjoining

Negation

Simple form	V-ing form
I couldn't adjoin you couldn't adjoin he couldn't adjoin we couldn't adjoin you couldn't adjoin they couldn't adjoin	I couldn't be adjoining you couldn't be adjoining he couldn't be adjoining we couldn't be adjoining you couldn't be adjoining they couldn't be adjoining
Perfect	V-ing perfect
I couldn't have adjoined you couldn't have adjoined he couldn't have adjoined we couldn't have adjoined you couldn't have adjoined they couldn't have adjoined	I couldn't have been adjoining you couldn't have been adjoining he couldn't have been adjoining we couldn't have been adjoining you couldn't have been adjoining they couldn't have been adjoining

Interrogative form

Simple form	V-ing form
could I adjoin? could you adjoin? could he adjoin? could we adjoin? could you adjoin? could they adjoin?	could I be adjoining? could you be adjoining? could he be adjoining? could we be adjoining? could you be adjoining? could they be adjoining?
Perfect	V-ing perfect
could I have adjoined? could you have adjoined? could he have adjoined? could we have adjoined? could you have adjoined? could they have adjoined?	could I have been adjoining? could you have been adjoining? could he have been adjoining? could we have been adjoining? could you have been adjoining? could they have been adjoining?

Interro-negative form

Simple form	V-ing form
couldn't I adjoin? couldn't you adjoin? couldn't he adjoin? couldn't we adjoin? couldn't you adjoin? couldn't they adjoin?	couldn't I be adjoining? couldn't you be adjoining? couldn't he be adjoining? couldn't we be adjoining? couldn't you be adjoining? couldn't they be adjoining?
Perfect	V-ing perfect
couldn't I have adjoined? couldn't you have adjoined? couldn't he have adjoined? couldn't we have adjoined? couldn't you have adjoined? couldn't they have adjoined?	couldn't I have been adjoining? couldn't you have been adjoining? couldn't he have been adjoining? couldn't we have been adjoining? couldn't you have been adjoining? couldn't they have been adjoining?