1. Willy's Vision of Ben: Throughout the play, Willy experiences visions of his deceased brother Ben, who represents the American Dream and the pursuit of wealth and success. Ben's presence and his advice to Willy foreshadow Willy's eventual downfall and his obsession with achieving the unattainable American Dream.
2. The Seeds: In Act 1, Willy repeatedly mentions planting vegetable seeds in the backyard, symbolizing his hopes and dreams for his sons, Biff and Happy. However, these seeds never grow, foreshadowing the failure of Willy's dreams and the disillusionment of his sons.
3. The Rubber Hose: Willy's recurring attachment to a rubber hose suggests the possibility of suicide. He keeps it hidden in the basement and mentions it several times, foreshadowing the tragic end that awaits him.
4. The Cracks in the Foundation: When Willy and Linda discuss the need to fix the cracks in the foundation of their house, it symbolizes the problems and weaknesses within their family and their lives. The cracks foreshadow the impending collapse of Willy's world and the disintegration of his family.
5. Biff's Trouble with Math: Biff's struggles with math and his inability to graduate from high school foreshadow his difficulties in finding success and fitting into the world that values material achievements. His academic challenges indicate the challenges he will face in his pursuit of the American Dream.
6. Willy's Failing Health: Willy's declining physical and mental health are evident throughout the play. He experiences hallucinations, delusions, and moments of confusion, foreshadowing his tragic breakdown and eventual mental collapse.
7. The Car Crash: The car accident that Willy has foreshadows his ultimate downfall. The accident becomes a metaphor for Willy's life and his inability to control his circumstances.
8. The "Death" Scene: In Act 2, Willy imagines his own funeral, foreshadowing his impending death. The scene provides a glimpse into Willy's inner thoughts and his fears about his legacy and the impact he has made on his family.
9. Bernard's Success: Bernard's success as a lawyer contrasts sharply with Biff and Happy's struggles, foreshadowing the challenges and disappointments that await Willy's sons in their pursuit of the American Dream.
Overall, the instances of foreshadowing in Death of a Salesman create a sense of foreboding and inevitability, hinting at the tragic events that will befall Willy and his family, while also highlighting the themes of unattainable dreams, disillusionment, and the hollowness of material success.