Hello, As for the content and meaning of your sentences, this is not important. The meaning is correct even if the words start with the same sound. Your instructor is concerned about the fluency of your sentences. Another way to think about this is how the sentence would sound if it were read out loud. While technically it is correct, it sounds a bit awkward. Improving the flow of the sentences enhances your writing, even if it is not strictly required. I hope this helps! Cheers, Hanna