I had visited Paris twice before I got married.

[Alice Chu]

Please tell me if my understanding is correct.
The following sentences refer to experiences rather than actions, so the simple past cannot be used here.
1. She never saw a bear before she moved to Alaska. (incorrect)
2. She had never seen a bear before she moved to Alaska. (correct)
3. I visited Paris twice before I got married. (incorrect)
4. I had visited Paris twice before I got married. (correct)

 

[Rover_KE]

They are all correct.

 

[5jj]

We frequently don't feel the need for a past perfect when the sequence of events is clear. 'Before' makes the sequence clear.

 

[Tdol]

In conversation, I'd use #3 rather than #4.