The lines that are written in past tense is " You must have walked and Did you leave nature well.
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What do you mean by Past Tense?</h3>
A tense is defined as the term which describe the particular time of an event. There are many languages through which the time is expressed not by verb but by the other part of speech.
A past tense is refers to as the tense that represent the action that has already happened or previously existed.
According to given sentences, the correct sentences are " You must have walked and Did you leave nature well because here the words walked and did shows as past tense and written as the third form of verb.
Rest all sentences are incorrect because they are written in the present tense.
Learn more about Tense, refer to the link:
brainly.com/question/11050269
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