1. When have the students discussed the pollution problems?

2. What have the thevies stolen the most in the national museum?

3. Whta will some people interview on TV?

4. How many languages are spoken in Canada?

5. What does your father water every morning?

6. Who did John invite to his birthday party last night?

7. Where is her mother preparing the dinner?

8. How often should you clean your teeth?

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1. How long have the students discussed the pollution problems?

2. What have the thieves stolen in the national museum?

3. Who will some people interview on TV?

4. How many languages do they speak in Canada?

5. What does your father water every morning?

6. Who did John invited to his birthday party last night?

7. Where is her mother preparing the dinner?

8. How often should we clean our teeth?