On this view, twins are probably an accidental by-product of a natural insurance policy against the risk of losing an embryo early in gestation.
根据这种观点，双胞胎很可能是一次在怀孕期间用自然保障方式防止流产的意外的副产品。
2
Acrylamide is present in many different types of food and is a naturalby-product of the cooking process.
丙烯酰胺存在于许多不同类型的食物中，是烹饪过程中的天然副产品。
3
The research team discovered a by-product of the oil refining process called cyclopentene. This was combined with a polymer to make a substance very similar to natural rubber.