Precontamination
初期污染
🗣️ 情景例句
How much does it weigh?
它多重？
One scabbed sheep will mar a whole flock.
一羊生癣，群羊受害。
It has never been explained why university students seem to enjoy practical jokes more than else.
谁也弄不清为什么大学生好像比任何人都更喜欢恶作剧。