Common objects can be pure or impure; it just depends whether or not they've been in contact with a source of impurity or not. Alright?

普通的事物可以是纯洁的或者不纯洁的;,原因只取决于它们是否,和一些不纯洁的来源有接触，对吧？

耶鲁公开课 - 旧约导论课程节选

If you oxidize any hydrocarbon, you generally produce heat, carbon dioxide, and water vapor, assuming a relatively pure fuel source.

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CAMBIA's approach is not pure open source, since the group relied on grants from foundations to develop the technology rather than on volunteers.

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Today, less than 5% of revenues come from emerging Big Data pure play vendors and open-source contributors such as Cloudera, Hortonworks and others.

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