Question

1. Why don't you go to the park together?
- Because I am too tired.

2. Why don't we go to the park together?
- Because I am too tired.

3. Why didn't you go to the park together?
- Because I was too tired.

4. Why didn't we go to the park together?
- Because I was too tired.
-------------------
Which dialogues are grammatical? Which ones are not? The patters are a bit difficult.

Answer 1

1and3 don't make sense. The others are fine.