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1. (-) They weren't in Rio last summer.

(?) Were they in Rio last summer?

2. ( - ) We didn't do our exercise this morning.

(?) Did you do your exercise this morning?

3. (-) My parents didn't come to visit me last July.

(?) Did your parents come to visit you last July?

4. (-)  The hotel wasn't very expensive.

(?) Was the hotel very expensive?

5. (-) I didn't have a bicycle when I was young.

(?) Did you have a bicycle when you were young?

6. (-) The children didn't go to the zoo yesterday.

(?) Did the children go to the zoo yesterday?

7. (-) Ernie didn't eat the last doughnut.

(?) Did Ernie eat the last doughnut?

8. (-) They didn't buy a new house last month.

(?) Did they buy a new house last month?

1. They were in Rio last summer.

(-) - They weren't in Rio last summer.

(?) - Were they in Rio last summer?

2. We did our exercise this morning.

(-)- We didn't do our exercise this morning.

(?) - Did we do our exercise this morning?

3. My parents came to visit me last July.

(-) - My parents didn't come to visit me last July.

(?) - Did my parents come to visit me last July?

4. The hotel was very expensive.

(-) - The hotel wasn't very expensive.

(?) - Was the hotel very expensive? 

5. I had a bicycle when I was young.

(-) - I didn't have a bicycle when I was young.

(?) - Did I have a bicycle when I was young?

6. The children went to the zoo yesterday.

(-) - The children didn't go to the zoo yesterday.

(?) - Did the children go to the zoo yesterday?

7. Ernie are the last doughnut 

(-) - Ernie didn't eat the last doughnut. 

(?) - Did Ernie eat the last doughnut?

 8. They bought a new house last month

(-) - They didn't buy a new house last month. 

(?) - Did they buy a new house last month?