English verb conjugation
COULD PINPOINT

Regular verb: pinpoint - pinpointed - pinpointed

Affirmation

Simple form	V-ing form
I could pinpoint you could pinpoint he could pinpoint we could pinpoint you could pinpoint they could pinpoint	I could be pinpointing you could be pinpointing he could be pinpointing we could be pinpointing you could be pinpointing they could be pinpointing
Perfect	V-ing perfect
I could have pinpointed you could have pinpointed he could have pinpointed we could have pinpointed you could have pinpointed they could have pinpointed	I could have been pinpointing you could have been pinpointing he could have been pinpointing we could have been pinpointing you could have been pinpointing they could have been pinpointing

Negation

Simple form	V-ing form
I couldn't pinpoint you couldn't pinpoint he couldn't pinpoint we couldn't pinpoint you couldn't pinpoint they couldn't pinpoint	I couldn't be pinpointing you couldn't be pinpointing he couldn't be pinpointing we couldn't be pinpointing you couldn't be pinpointing they couldn't be pinpointing
Perfect	V-ing perfect
I couldn't have pinpointed you couldn't have pinpointed he couldn't have pinpointed we couldn't have pinpointed you couldn't have pinpointed they couldn't have pinpointed	I couldn't have been pinpointing you couldn't have been pinpointing he couldn't have been pinpointing we couldn't have been pinpointing you couldn't have been pinpointing they couldn't have been pinpointing

Interrogative form

Simple form	V-ing form
could I pinpoint? could you pinpoint? could he pinpoint? could we pinpoint? could you pinpoint? could they pinpoint?	could I be pinpointing? could you be pinpointing? could he be pinpointing? could we be pinpointing? could you be pinpointing? could they be pinpointing?
Perfect	V-ing perfect
could I have pinpointed? could you have pinpointed? could he have pinpointed? could we have pinpointed? could you have pinpointed? could they have pinpointed?	could I have been pinpointing? could you have been pinpointing? could he have been pinpointing? could we have been pinpointing? could you have been pinpointing? could they have been pinpointing?

Interro-negative form

Simple form	V-ing form
couldn't I pinpoint? couldn't you pinpoint? couldn't he pinpoint? couldn't we pinpoint? couldn't you pinpoint? couldn't they pinpoint?	couldn't I be pinpointing? couldn't you be pinpointing? couldn't he be pinpointing? couldn't we be pinpointing? couldn't you be pinpointing? couldn't they be pinpointing?
Perfect	V-ing perfect
couldn't I have pinpointed? couldn't you have pinpointed? couldn't he have pinpointed? couldn't we have pinpointed? couldn't you have pinpointed? couldn't they have pinpointed?	couldn't I have been pinpointing? couldn't you have been pinpointing? couldn't he have been pinpointing? couldn't we have been pinpointing? couldn't you have been pinpointing? couldn't they have been pinpointing?