English tip: When to use past perfect tense: 1. Something occurred before another action in the past/Something happened before a specific time in the past. For example: I had never known what love is until I met my beautiful wife. 2. Something started in the past and continued up until another action in the past. For example: She had been living with her family until she moved to New York. 3. You can use specific time periods with past perfect. However, a simple past would have been sufficient. For example: She had been/was sentenced to two-years jail in 2001 for robbery. If a specific time cannot be identified, simple past cannot be used. She had never seen snow before she moved to New York. (correct) She never saw snow before she moved to New York. (incorrect- it’s a lack of experience and not a specific action at a specific time.)