The only condition is that they should have no paint and oil spots and burning marks.

唯一的一个条件是：这些轮胎没有任何涂染、油污以及燃烧的痕迹。

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Even if you can't see any stains, it's possible that lingering oil spots will oxidize and become noticeable (and permanent), so keep that in mind when deciding what needs washing.

即便你没有看到衣服上有任何污渍，也有可能渗透的油点将会氧化很明显（有时，油点是永久不褪去的）。因此，切记，知道什么样的衣服是必须清洗后再保存的。

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It is alsodesirable to be used for removing heavy oil spots off polyester, cotton fabrics or polyester silk imitations in alkali bath, as well as for pretreatment of oily silk yarn.

在强碱浴用于去除涤、棉及涤仿绸上的重油垢及油丝的前处理也甚为理想；

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The challenge is to pick out oil from other dark spots, such as shadows made by clouds or patches of seaweed.

VOA: standard.2010.07.05

Similarly, oil produced from shale will allow the U.S. to un-hook from the spigot of oil supplied from global hot spots.

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Video shot by the robotic submarines (a.k.a. remote operated vehicles or ROVs) seems to indicate that oil is leaking from three spots in a pipe that is laying on the seafloor.

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Imaging techniques are so good that geologists can approximate standing inside a rock formation to look for the spots most likely to hold oil.

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