'Of Mice and Men' what things does Lennie do or say that show he is mentally retarded?

In "Of Mice and Men," Lennie shows signs of being mentally challenged through his limited cognitive ability, childlike behavior, and difficulty understanding social cues. He often relies on George to guide him and struggles with processing information or making decisions independently. Lennie's repetition of phrases, fixation on soft things, and lack of understanding of consequences further illustrate his cognitive limitations.