1. My mother gave me (beautiful) gifts.→ The root word of beautiful is beauty. 2. The salesman is (selling) nice jewelry items.→ The root word of selling is sell.3. Martha is (unhappy) that she cannot buy the best gift for her mother's birthday.→ The root word of unhappy is happy.4. She (thanked) her father for (helping) her.→ The root word of thanked is thank. → The root word of helping is help.5. Her father (showed) her the best gift shop in town.→ The root word of showed is show.When we say root word, it's the main part of a word that has the basic meaning. It's the word without any prefixes or suffixes added.