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2. I'm at home tonight, but wasn't home last night.

3. Olga is busy tonight, but wasn't busy yesterday.

4. We're in class this morning, but weren't in class yesterday morning.

5. Tom is at the library tonight, but wasn't at the library last night.

6. It's cold this week, but wasn't cold last week.

7. Alex and Rita are at work this afternoon, but weren't at work yesterday afternoon.

8. Mr. and Mrs. Jones are at home tonight, but weren't at home last night

9. You're in class today, but weren't at class yesterday.

10. Dr. Ruckman is in her office this afternoon, but wasn't in her office last afternoon.

4)

2. A: Was Mr. Yamamoro absent from class yesterday?

B: No, he wasn't.

3. A: Were Alex and Sue at home last night?

B: Yes, they were.

4. A: Were you nervous the first day of class?

B: Yes, I was.