Answer:
Foreshadowing is a narrative element used by an author to provide their readers with subtle hints of major events that probably will occur as the story-line of the novel progresses.
Gifts and Kind Acts by Boo Radley – The Mysterious Neighbor.
When the children discover gifts for them, find Jem’s pants mended, the readers are given a hint that these actions may be performed by Radley, saying that he is unlike what people perceive him to be. Later in the book, he protects Scout and Jem from Bob Ewell.
Killing of the Mad Dog
The shooting of the mad dog by Atticus is symbolic that perhaps, the real Tom Robinson might meet the same fate. Coincidentally, the dog’s name is Tom Johnson, which is quite similar to his name. This foreshadows that someone innocent is going to die.
Racial Discrimination
In the story, innocent Tom gets killed, simply because he is black. This also marks the struggle of black Americans for their freedom from slavery. Also, it indicates how innocence is killed simply in the name of racial discrimination, and people of the town simply assume that the crime was committed by Tom.