Final answer:
The comma in the sentence 'When I went to Chicago, the weather was terrible,' is correctly placed. The sentence is a complex sentence with the dependent clause before the independent clause, thus necessitating a comma.
Step-by-step explanation:
The placement of the comma in the sentence, 'When I went to Chicago, the weather was terrible,' is correct. This sentence is a complex sentence that comprises an independent clause ('the weather was terrible') and a dependent clause ('When I went to Chicago'). In such sentences, if the dependent clause comes before the independent clause, it should be followed by a comma. Therefore, the use of the comma in this context is perfectly correct.
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