difficult to forgive difficult to form difficult to formulate difficult to fully difficult to gain difficult to gather difficult to gauge difficult to generalize difficult to get difficult to get a job difficult to get out difficult to get out of difficult to get people difficult to get rid difficult to get through difficult to get used difficult to give difficult to give up difficult to go difficult to go back difficult to grasp difficult to grow difficult to guess difficult to handle difficult to have difficult to heal difficult to hear difficult to help difficult to hide difficult to hit difficult to hold difficult to identify difficult to ignore difficult to imagine difficult to imagine how difficult to imagine what difficult to imitate difficult to implement difficult to improve difficult to increase difficult to install difficult to integrate difficult to interpret difficult to isolate difficult to judge difficult to just difficult to justify difficult to keep difficult to keep track difficult to keep up difficult to kill difficult to know difficult to know exactly difficult to learn difficult to leave difficult to let difficult to listen difficult to live difficult to locate difficult to look difficult to lose difficult to love difficult to machine difficult to maintain difficult to make difficult to make out difficult to manage difficult to maneuver difficult to manipulate difficult to manufacture difficult to master difficult to match difficult to me difficult to measure difficult to meet difficult to mix difficult to model difficult to monitor difficult to motivate difficult to move difficult to name difficult to navigate difficult to negotiate difficult to not difficult to notice difficult to observe difficult to obtain difficult to open difficult to operate difficult to organize difficult to overcome difficult to overstate difficult to pass difficult to pay difficult to penetrate difficult to persuade difficult to photograph difficult to pick difficult to pin