Before revision: A hook is a tool consisting of a length of material, typically metal, that contains a portion that is curved or indented, such that it can be used to grab onto, connect , or otherwise attach itself onto another object .
After revision: A hook is a tool consisting of a length of material, typically metal, that contains a portion that is curved or indented, such that it can be used to grab , connect or in any way/bent back attach itself onto another object .