Final answer:
The main clause in the sentence 'When I go to the supermarket, I will buy bread' is 'I will buy bread'. The main clause contains a subject and verb and delivers a complete thought.
Step-by-step explanation:
In the sentence 'When I go to the supermarket, I will buy bread', the main clause is 'I will buy bread'. In English grammer, a main clause is a group of words that contains a subject and verb and delivers a complete thought. In this case, the subject is 'I' and the verb is 'will buy'. The phrase 'When I go to the supermarket' is a dependent clause which provides additional information but cannot stand alone as a sentence.
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