IMPORTANT Specific Times with the Past Perfect

Unlike with the Present Perfect, it is possible to use specific time words or phrases with the Past Perfect. Although this is possible, it is usually not necessary.

Example:

•She had visited her Japanese relatives once in 1993 before she moved in with them in 1996.
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If the Past Perfect action did occur at a specific time, the Simple Past can be used instead of the Past Perfect when "before" or "after" is used in the sentence. The words "before" and "after" actually tell you what happens first, so the Past Perfect is optional. For this reason, both sentences below are correct.

Examples:

•She had visited her Japanese relatives once in 1993 before she moved in with them in 1996.
•She visited her Japanese relatives once in 1993 before she moved in with them in 1996.