Key Difference: Forget is to dismiss something from mind. Forgot is the simple past tense of forget. Whereas, forgotten is the past participle of forget.

Forgot is the past tense of forget. To forget is an act of not remembering something. It is a state when something gets missed from the mind. Forgot is used when the act of forgetting is addressed in the past. Forgot is also used as past participle of forget. For example, Martha forgot to bring her book. In this sentence, Martha has completed the act of forgetting her book. So, forgot is used to indicate the past nature of the act. This can also be written as, Martha had forgot to bring her book. This means, Martha forgot to bring her book and it is being expressed with perfect aspect.

Forgotten is the past participle of forget. Past participles are the words that make the sentence complete by expressing perfect aspect. Moreover, these are the words which are used for a more formal representation. Past participles are used with auxiliary verbs like, have, had or have. For example, Martha had forgotten to bring her book. Here, the meaning of the sentence is same; however, it is being expressed more formally and with a perfect aspect of the book being forgotten.

Many people get confuse about the use of ‘forgot’ and ‘forgotten’. However, both the words are correct to use as per the requirement, provided that an auxiliary verb must be used with the word forgotten.

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