然而，味精本身并非天然食品。
这即说，这些授粉的蜜蜂并非天然所需。
That being said, these pollinating bees are not a requirement for pollinating crops naturally.
他们鉴定出四种不同的含铅物质，其中两种是人工合成的，并非天然物质。
They identified four different lead-based substances, two of which were man-made, not natural.
应用推荐