1) Connotation refers to the emotional or cultural associations of a word, while denotation is the strict dictionary definition. 2) Paraphrase expresses the meaning of a word, phrase, or sentence using different but semantically equivalent words. It can be lexical, using a synonym, or structural, rephrasing the syntax. 3) Entailment is a semantic relationship where the truth of one sentence implies the truth of the other, but not vice versa, such as "George killed the spider" entailing "The spider is dead."