A firefighter was overcome by fumes at a blaze in a plastics factory.一名消防队员在一家塑料厂的火灾中被烟熏倒了.In the artical, fire retarding methods for plastics are simply introduced.本文简要介绍了塑料的阻燃方法.The color deviation is a very important ...
这本书是有关于地磁的.This book is about the earth's magnetism.他们发现, 牛在吃草或是休息的时候, 总是面向地磁的南极或是北极.And, when grazing or resting, cows tended to face either magnetic north or south....