activity on arrow的用法和样例：
- There is a lot of activity on the stock exchange.
- There had been little activity on the street.
- That professor had ever been very active on the world scene.
- Good follow up activity on the correction action effectiveness.
(2) + 有效地跟进改善行动的有效性.
- The Anti-Tumor Activity on Alkaloid of Sophora Favescens Ait.