Upon the inquiry I found out that I had _______ the car.

Mistake

Mistaken

Mistook

Mistaking

All of these

I found out that I had mistaken the car.

مجھے پتہ چلا کہ میں نے گاڑی کو غلط کر دیا تھا۔

Here 'had' indicates past perfect tense.

We generally use third form (mistaken) of verb in this tense.

First form: Mistake

Second form: Mistook

Third form: Mistaken

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