Answer:
1. When bob saw Mrs. Smith, she stood on her front porch. She held a broom. Mrs. Smith waved at Bob when she saw him.
2. Sally ate dinner last night when someone knocked o the door.
3. I began to study at seven last night. Fred came at seven-thirty. I studied when Fred came.
4. When I studied last night, Fred dropped by to visit me.
5. My roommate’s parents called him last night while we watched TV.
6. My mother called me around five. My husband came home a little a after that. When he came home, I talked to my mother on the phone.