下面两句均摘自高中英语北师大版必修三的第40页:
1. Last August, city officials interviewed about 500 residents to find out people’s attitudes to protecting the environment and what actions they had taken.
2. Unfortunately, not as many who took part had taken action to save water and energy in their homes.
上面两句为什么一个用的是 take acitions,另一个用的是 take action 呢?这样用的 action 用单数或复数都可以吗?有没有区别?