English verb conjugation
COULD RETEST

Regular verb: retest - retested - retested

Affirmation

Simple form	V-ing form
I could retest you could retest he could retest we could retest you could retest they could retest	I could be retesting you could be retesting he could be retesting we could be retesting you could be retesting they could be retesting
Perfect	V-ing perfect
I could have retested you could have retested he could have retested we could have retested you could have retested they could have retested	I could have been retesting you could have been retesting he could have been retesting we could have been retesting you could have been retesting they could have been retesting

Negation

Simple form	V-ing form
I couldn't retest you couldn't retest he couldn't retest we couldn't retest you couldn't retest they couldn't retest	I couldn't be retesting you couldn't be retesting he couldn't be retesting we couldn't be retesting you couldn't be retesting they couldn't be retesting
Perfect	V-ing perfect
I couldn't have retested you couldn't have retested he couldn't have retested we couldn't have retested you couldn't have retested they couldn't have retested	I couldn't have been retesting you couldn't have been retesting he couldn't have been retesting we couldn't have been retesting you couldn't have been retesting they couldn't have been retesting

Interrogative form

Simple form	V-ing form
could I retest? could you retest? could he retest? could we retest? could you retest? could they retest?	could I be retesting? could you be retesting? could he be retesting? could we be retesting? could you be retesting? could they be retesting?
Perfect	V-ing perfect
could I have retested? could you have retested? could he have retested? could we have retested? could you have retested? could they have retested?	could I have been retesting? could you have been retesting? could he have been retesting? could we have been retesting? could you have been retesting? could they have been retesting?

Interro-negative form

Simple form	V-ing form
couldn't I retest? couldn't you retest? couldn't he retest? couldn't we retest? couldn't you retest? couldn't they retest?	couldn't I be retesting? couldn't you be retesting? couldn't he be retesting? couldn't we be retesting? couldn't you be retesting? couldn't they be retesting?
Perfect	V-ing perfect
couldn't I have retested? couldn't you have retested? couldn't he have retested? couldn't we have retested? couldn't you have retested? couldn't they have retested?	couldn't I have been retesting? couldn't you have been retesting? couldn't he have been retesting? couldn't we have been retesting? couldn't you have been retesting? couldn't they have been retesting?