be adj to do还是to be done

例如：
This machine is very easy_.Anybody can learn to use it in a very short time.
为什么填to use而不是to be used

---

to use

因为此句型中句子主语是不定式的逻辑宾语，则胡斗 而做拆非逻辑主语

再如：
He is easy to get along with
The question is easy to answer
The apple is good to eat.

【希望帮助到你，若有疑问，可以追问~~~
祝你学习进步，更上一层楼！孙磨(*^__^*)】

---

This machine is very easy（for us）to use

省略了 for us，我们槐禅羡和使用铅拍之间袭扒是主动的关系

---