This question is incomplete. Here's the complete question.
Read Milkweed, by Jerry Spinelli.
Why are people unable to go out at night in the city of Warsaw?
Answer:
Spinelli´s novel is about an orphan boy living on the streets of Warsaw, Poland during the Holocaust in World War II. At night, only the patrols would be out in Warsaw, which made it a dangerous time for him and the other Jewish orphans.
Step-by-step explanation:
When the main character becomes friends with a girl named Janina, he waits for her despite that danger.