例句與造句

1. Adventitious presence is a key issue in the debate over regulation of biotechnology.
2. But there's always adventitious presence, which means small amounts of unintentional presence through pollen flow and physical mixing ."
3. Some of the lots could present a small, adventitious presence of genetically modified organisms, but well below the standards which are generally accepted.
4. It's difficult to find adventitious presence in a sentence. 用adventitious presence造句挺難的