able和ful结尾的形容词

　　Study on the Rule and Mechanism of the Quality Change of DrinkableWater

　　饮用水水质变化规律和机理的研究

　　This system is the most ideal drinkable water production facility in China.

　　该系统是目前国内最理想的饮水设备。

　　It is often helpful for teachers to shadow managers in industry.

　　教师跟随业界的管理人员实地学习，常常会很有收获。

　　I called the police but they weren't very helpful.

　　我叫了警察，但他们不太肯帮忙。