Final answer:
The subject in the sentence '1. Stop the car' is the implied 'you'. In English, commands often have an understood 'you' as the subject.
Step-by-step explanation:
In the given sentence, '1. Stop the car', the subject is actually implied. In English, commands often have an understood 'you' as the subject. So, in this sentence, the subject is 'you', even though it's not stated explicitly. The action 'Stop' is what the subject (you) is being asked to do, and 'the car' is the object of this action.
Answer:you
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