第一部分 翻译（出处为教材）

1）Storage facilities for crude, natural gas, and light hydrocarbon products are an important element in all pipeline and tanker transportation systems. Storage allows flexibility in pipeline and refinery operations and minimizes unwanted fluctuations in pipeline throughput and product delivery.

2）A refinery must operate continuously to be efficient, though its throughput can be reduced if necessary; enough crude to feed the refinery must be available.

3）Large crude storage tanks often have a floating roof that moves up and down with liquid level in the tank to minimize vapor losses.

第二部分 听力

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