There are numerous examples of these literary techniques in the two works. Here are a few.
Foreshadowing: Bob Ewell threatens to "get" Atticus no matter how long it takes. His threat foreshadows his subsequent attack on Jem and Scout. Lennie's accidentally killing the mouse foreshadows his accidentally killing Curley's wife
Contrast: Atticus' understanding and acceptance of others and his refusal to judge them based on their race or social class contrast Aunt Alexandra's prejudice and snobbishness. Slim's kindness and gentleness contrasts Curley's viciousness.
Climax: Scout finally meets Boo Radley. George shoots Lennie.
Simile: During the fire when Miss Maudie's house burns, Scout describes the smoke as "rolling off our house . . . like fog off a riverbank." Steinbeck writes, ". . . the rabbits sat as quietly as little gray, sculptured stones."
Metaphor: Boo Radley is "a malevolent phantom." George and Lennie want to live off "the fat of the land," a metaphor for the abundant crops the Earth produces for us.
Parallels: Tom Robinson parallels the mockingbirds Atticus says must not be shot; like them, Tom is innocent, gentle, and harmless. Slim's shooting his dog parallels George's shooting Lennie; both are very pain-filled acts of kindness
Archetypes: Atticus can be seen as the archetype of courage and integrity. George and Lennie are archetypes of those who live on the fringes of society, never experiencing the good things life has to offer.
The climax is wrong. The climax is when the jury finds Tom guilty