Precontamination
初期污染
🗣️ 情景例句
I have a new puppy and he has an excellent temperament.
我有只新的小狗，它的脾气很好。
His working is behind schedule.
他的工作比预定的进度落后了。
I heard that you're getting married, Congratulations.
听说你要结婚了，恭喜！