Indirect questions in writing

- When does the course start?
- Could you tell me ❌

- Do I need to do a level test?
- Please let me know ❌

- How much does the course cost?
- Would you mind telling me ❌

- Do you have native teachers?
- Could you tell me ❌

- When do your courses begin?
- I would be grateful if you could tell me ❌