In which of the following situations is it not appropriate to use commas? (a.)before a coordinating conjunction (b.)to separate items in a list (c.)to introduce a list (d.)to set off introductory material

Match the description to the term. 1. textbooks conference usage 2. elements surround a word which clarify the meaning casual usage 3. the way in which english is used context 4. family and friends frozen usage 5. friends at a football game formal usage 6. teachers and employers intimate usage 7. making an appointment usage