It's important that the grain surface is smooth .

光滑的皮纹非常重要。

Or it could be made into a dusting powder for fingerprint detection on shiny or patterned surfaces, where normal fingerprint powder is hard to see.

或者可以被制成一种隔离剂用于光滑或图形的指纹检测，普通指纹粉在这些中很难探测。

Sometimes the surfaces are such that it becomes a little difficult to figure out which side is the shiny side and which is the rough side.

有的情况使得很难分辨哪一是光滑，哪一是粗糙。

The sun might make you ruddier but racing down a " gutter" on a surface slick as " butter" even if you have to " crash" could help you make a " splash" .

或许炙热的阳光会使你烦躁，又或许你需要被“碰擦”了才能引起大家的注意，但你终归需要克服这光滑的槽，勇敢冲下来。