Topochemotaxis
趋化源性
🗣️ 情景例句
It's seventy-five cents for adults and thirty cents for children under twelve.
大人75美分，12岁以下的小孩30分。
Obedience is the first duty of a soldier.
服从是军人的第一职责。
Is it okay to smoke in the office?
在办公室里抽烟可以吗？