John left me, and a few minutes later I saw him from my window walking slowly across the grass arm in arm with Cynthia Murdoch. 
John was a liar and cheated on me with Cynthia. 
mnli hypothesis: John was a liar and cheated on me with Cynthia.  premise: John left me, and a few minutes later I saw him from my window walking slowly across the grass arm in arm with Cynthia Murdoch. 