Dear sir,
Last week, I bought a robot from your company. However, I am not satisfied with it.
First of all, I am unhappy with its batteries. They last for one week at most. I think they should last at least one month.
The quality of this robot is not up to standard either. A good robot should only need checking every eight months. My robot has already stopped working completely. I don't know what's the matter with it.
I regret having bought a robot like this. You'd better send me a new one, or I would like to get my money back. I hope to receive your reply soon. Yours faithfully,
Jack
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词组/短语积累:
① buy sth. from… 从 ……买
② be (not) satisfied with 对……(不)满意
③ be unhappy with 对……不满意
④ at most 最多
⑤ at least 最少
⑥ be not up to standard (没有)达到标准
⑦ stop doing sth. 停止做某事
⑧ had better do sth. 最好做某事
⑨ get sth. back 拿回某物
⑩ receive one's reply 收到某人的回复
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本文是一封投诉信。按照写作要求,信中提到了自己想要投诉的具体原因以及自己的要求。文章包含了所有的要点、内容完整、句意通顺,层次清晰、有逻辑。文章用了大量地道的短语和句型,为文章增色不少。