“一辆汽车从伦敦某条街道起飞，降落在另一条随机的街道上是不太可能发生的。”一流的航空工程师格雷教授这样说。

"A car that takes off from some London street and lands in another random street is unlikely to happen," says Prof Gray, a leading aeronautical engineer.

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就拿PubMed上的1900万份研究论文来说，一小部分堪称一流：大型，随机，受控的临床试验和结果的荟萃分析与论文提供的数据相当吻合。

Take, for example, those 19 million studies on PubMed. Some are gold-standard research: large, randomized, controlled clinical trials or meta-analyses that carefully parse millions of data points.

youdao

就拿PubMed上的1900万份研究论文来说，一小部分堪称一流：大型，随机，受控的临床试验和结果的荟萃分析与论文提供的数据相当吻合。

Take, for example, those 19 million studies on PubMed.Some are gold-standard research: large, randomized, controlled clinical trials or meta-analyses that carefully parse millions of data points.

youdao