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I'd be happy to help you with the writing exercise. Here are the answers: I. Arrange the following words to make a meaningful sentence. 1. This vaccine can prevent the disease cancer. 2. The scientists did not invent the clock last year. (Note: The original sentence "scientists/ invented /the/ clock /last / the /year /./" seems to be incorrect. The invention of the clock dates back to ancient times, and it's unlikely that scientists invented it last year.) 3. Although the weather was bad, it did not delay the traffic. II. Complete the second sentence so that it means the same as the sentence before 1. Study harder or you can't pass the next exam. -> If you don't study harder, you can't pass the next exam. 2. I am one of her friends. -> I am her only friend. (Note: The original answer choice "I am her friends" is incorrect. The correct answer is "I am her only friend" or "I am one of her friends", but "her only friend" is more idiomatic.) 3. "I will visit my hometown tomorrow". She said -> She said that she would visit her hometown the next day. 4. Nobody in my class is better at English than Ba. -> Ba is the best at English in my class.