Answer: This is from grade saver: "Before Curley goes to the hospital, he agrees to pretend that he has caught his hand in a machine. Slim threatens to tell others what really happened if Curley does not agree to this. Lennie is afraid that he has done something bad, but George reassures him that he hasn't as the chapter closes. Slim likes George and Lennie and does not want to see them fired. Slim is also a fair and just man. He knew that Curley deserved what happened to him."
Hope this helps...... Stay safe and have a Merry Christmas!!!!!!! :D