This is the answer , and I am so sure.
When they commit a severe crime. That’s what I think.
At the beginning of the play Iago persuades Roderigo to tell the truth to Desdemona's father and while Roderigo manages to confess Iago just pasees and hides trying to not get involved. And in order to avoid getting to the jail agai he tries to get closer to <span>Othello and poses as his friend. I bet these two situations will help you.</span>
This is personification. It means that human qualities are attributed to non-human entities. Here it says that the contemporary frustration nourishes the movement, which is a personification.
When the narrator said "Grandfather believed that a well-rooted tree was the color of money", he meant that the tree gave Grandfather food for him and his family to survive.
:)