Elementary

1. Do you think … ?
2. How do you feel about … ?
3. In your opinion, … ?
4. Please tell me your opinion on …
5. What do you think about … ?
6. What’s your opinion on … ?

Pre-intermediate

1. Do you (also) think that … ?
2. Do you believe that … ?
3. Do you have an opinion on … ?
4. Do you have any opinions on/about … ?
5. In your experience, … ?
6. In your honest opinion, … ?
7. What’s your view on … ?
8. Would you agree that … ?

Intermediate

1. Can you give me your thoughts on … ?
2. Do you (dis)approve of … ?
3. Do you agree with the opinion that … ?
4. Do you have any views on … ?
5. Do you share the/my view that … ?
6. If I asked your opinion about … , … ?
7. If I said … , … ?
8. I’d like (to hear) your views on …
9. I’m sure you’d agree that …
10. What are your feelings about … ?
11. What are your views on … ?