English verb conjugation
COULD YIELD

Regular verb: yield - yielded - yielded

Affirmation

Simple form	V-ing form
I could yield you could yield he could yield we could yield you could yield they could yield	I could be yielding you could be yielding he could be yielding we could be yielding you could be yielding they could be yielding
Perfect	V-ing perfect
I could have yielded you could have yielded he could have yielded we could have yielded you could have yielded they could have yielded	I could have been yielding you could have been yielding he could have been yielding we could have been yielding you could have been yielding they could have been yielding

Negation

Simple form	V-ing form
I couldn't yield you couldn't yield he couldn't yield we couldn't yield you couldn't yield they couldn't yield	I couldn't be yielding you couldn't be yielding he couldn't be yielding we couldn't be yielding you couldn't be yielding they couldn't be yielding
Perfect	V-ing perfect
I couldn't have yielded you couldn't have yielded he couldn't have yielded we couldn't have yielded you couldn't have yielded they couldn't have yielded	I couldn't have been yielding you couldn't have been yielding he couldn't have been yielding we couldn't have been yielding you couldn't have been yielding they couldn't have been yielding

Interrogative form

Simple form	V-ing form
could I yield? could you yield? could he yield? could we yield? could you yield? could they yield?	could I be yielding? could you be yielding? could he be yielding? could we be yielding? could you be yielding? could they be yielding?
Perfect	V-ing perfect
could I have yielded? could you have yielded? could he have yielded? could we have yielded? could you have yielded? could they have yielded?	could I have been yielding? could you have been yielding? could he have been yielding? could we have been yielding? could you have been yielding? could they have been yielding?

Interro-negative form

Simple form	V-ing form
couldn't I yield? couldn't you yield? couldn't he yield? couldn't we yield? couldn't you yield? couldn't they yield?	couldn't I be yielding? couldn't you be yielding? couldn't he be yielding? couldn't we be yielding? couldn't you be yielding? couldn't they be yielding?
Perfect	V-ing perfect
couldn't I have yielded? couldn't you have yielded? couldn't he have yielded? couldn't we have yielded? couldn't you have yielded? couldn't they have yielded?	couldn't I have been yielding? couldn't you have been yielding? couldn't he have been yielding? couldn't we have been yielding? couldn't you have been yielding? couldn't they have been yielding?