At first, they thought he was doing something bad, but later they realized he was actually writing something in his notebook, taking advantage of the streetlight overhead.

起初，他们以为他在做坏事，但后来他们意识到他实际上是在利用头顶的路灯在笔记本上写东西。

youdao

For the first two days in my flat, he was very calm, and spent all his time reading and smoking, and writing in a little black notebook.

他在我寓所住的前两天神态非常平静，一直在读书，吸烟，在一个黑色的小笔记本上写东西。

youdao