সহায়িকা

The correct verb form to complete the sentence is realized. The complete sentence should be: "It's time you realized your mistakes."
Explanation
The phrase "It's time" followed by a subject (in this case, "you") requires the past simple tense (also called past indefinite tense) for the main verb that follows.
This structure is used to express that something should be happening now, or has been due for a while, and it is a good moment to do it. It has a present or future meaning, despite using a past tense verb.
The past simple form of the verb "realize" is "realized".

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