1·Theory and some observational data pointed to the likelihood that they were ubiquitous.
理论和一些观测数据则指向他们曾经普遍存在的可能性。
2·Some observations of clouds support model predictions, but direct observational evidence is still limited.
一些云观测支持模式的预报，但是直接的观测证据仍然很有限。
3·Nonetheless, the study provides “the most convincing observational test” that the mix of stars -- heavyweights and lightweights -- varies dramatically from one type of galaxy to another, says Ellis.
尽管如此，这项研究提供了“最令人信服的观测试验”，群星--重量级的，轻量级的--从一种星系到另一种，引人注目，各式各样；埃利斯说。
4·Scientists have carefully checked these observations to exclude observational errors and other influences - such as the urban heat island effect and localised warming due to land surface changes.
科学家们谨慎地监测那些观测，以排除观测误差和其它影响，诸如城市的热岛效应和由于地表变化导致的局部升温。
5·Researchers created a new supercomputer model, based on observational data and the "Lambda Cold Dark Matter" theory of the universe.
研究人员在观测数据和兰姆达冷暗物质模型的基础上构建了一个新的计算模型。
1·Cultivating drawing talent can become an essential tool to improve people's observational skills in fields where the visual is important.
在强调视觉重要性的领域，培养绘画才能可以成为提高人们观察能力的重要工具。
2·The following optical illusions will definitely test your imagination and observational skills to the Max so test yourself to see how you perform.
以下的视错觉一定会最大限度地考验你的想象力和观察能力，所以自己测试下，看看你的表现吧。
3·The subsequent two decades have seen much observational and theoretical work aimed at this problem.
接下来的二十年中，有许多观察和理论的研究是专注在这问题上。
4·But the authors acknowledged that they could not account for all possible variables, and cautioned that it was an observational study that draws no conclusions about cause and effect.
不过，作者们承认未能一一证明所有可能的变化因素，并提醒这是项观察研究，不能就此得出这两者之间存在因果关系的结论。
5·Since NHANES III was an observational study and not a clinical trial, no definite conclusions about cause and effect were possible, says Dr. Cohen.
科恩博士说：“NHANES III是一项观察上的研究而不是一次临床试验，所以，关于因果没有一个确定的结论是可能的。”