次级来源，第二手来源

第二手来源，次级来源；二次文献

secondary storage───[计]二级存储器；[计]辅助存储器

second-source───n.第二资源

secondary cause───次要因素

secondary role───次要作用

secondary colours───合成色

secondary moderns───现代中学

secondary product───副产品

Don't rely exclusively on a single secondary source for information or opinion in a research paper.───在一篇研究论文中，不要在信息或观点上排他性地依赖单独一处二手资料。

Meat is, at best, a secondary source of essential elements.───肉类充其量不过是身体基本要素的次要来源。

the design and manufacture of a set of secondary source are finished.───次级声场的理论推导并完成了引入次级声场装置的设计、制造。

The happiness that is derived from some secondary source is never very deep.───要从次要的某个源头得到的是很浅的快乐.

Secondary sources for A level essays will probably be the work of historians.

Meat is, at best, a secondary source of essential elements.

Historians use a wide range of primary and secondary sources for their research.

The distinction between primary and secondary sources will not always be immediately obvious to the pupil.

Agriculture, deforestation and the other secondary sources of greenhouse gases are critical to many.

Clearly distinguish between primary and secondary sources, and between the different types of history books.

Secondary sources, in contrast(http://sentencedict.com/secondary source.html), are interpretations of the past produced at a later date.

Don't rely exclusively on a single secondary source for information or opinion in a research paper.

You can't just rely on secondary sources for your research into her life history - you ought to look at primary sources such as her letters and diaries.