Sure! Here are the answers to the sentences you provided:

1. **Do all the wash, please. (be)**
**Answer:** **Please be sure to do all the wash.**

2. **Mike thought that we were married. (under)**
**Answer:** **Mike was under the impression that we were married.**

3. **The only thing that kept us out of prison was the way he spoke the local dialect. (but for)**
**Answer:** **But for the way he spoke the local dialect, we would have been in prison.**

4. **Spending a week in Nha Trang is going to be great.**
**Answer:** **We are going to have a great time spending a week in Nha Trang.**

5. **Jane has an appointment for a haircut this evening.**
**Answer:** **Jane is having her hair cut this evening.**

6. **It was too late for us to do anything.**
**Answer:** **Everything was too late for us to do anything.**

7. **Only two out of the five rooms we have booked have air conditioning.**
**Answer:** **We have booked five rooms, only two have air conditioning.**

8. **Everyone knows that taking exercise is good for your health.**
**Answer:** **Taking exercise is widely known to be good for your health.**

Let me know if you need further assistance!