1·Images are resized to stay within the column and all the extraneous material on a page is removed.
图片会做调整以保持在列，而页面上所有的多余材料会被取出。
2·This study validated the ability of a filter to effectively remove undesired extraneous material even with an inoculant pellet embedded in the filter.
本研究证实，即使安置有一孕育块，过滤器也具有有效地去除不希望的外来物质的能力。
3·All these etymological doublets indicate that the Peking dialect is comprised of a basic native word stock overlaid with one or more strata of extraneous material.
所有这些二词一组的同源词说明了，北京话的基本词汇层并非只有一层。最后一句搞不清啦，意译了，呵呵。
4·To avoid such errors in the new study, they tagged each Neanderthal DNA strand with a unique molecular bar-code, to distinguish it biochemically from any extraneous genetic material.
因此在新的研究中，为避免再出现这种错误，他们将每一条尼安德特人的DNA都标记出来，以区别于所有外来的遗传物质。