1. TEACHERS are always busy ( NOUN )
2. THEY are always busy ( PRONOUN )
3. They are always BUSY ( ADJECTIVE )
4. They are ALWAYS busy ( ADVERB )
5. They ARE always busy ( VERB )
6. Teachers AND Students are friends ( Conjunction )
7. Teachers work AT the local college ( Preposition )
8. WOW ! that is awesome ( Interjection )