Final answer:
The subject of the sentence is 'I', the person who forgot the lunch money. The subject is the noun, pronoun, or noun phrase that performs the action of the verb.
Step-by-step explanation:
The subject of the sentence is 'I', the person who forgot the lunch money. In English grammar, the subject of a sentence is the noun, pronoun, or noun phrase that performs the action of the verb. It usually answers the question 'who' or 'what' is doing the action. In this case, 'I' is the subject because the person speaking is the one who forgot their lunch money.
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