過去完了形の使い方

In class the other day someone was asking about past perfect tense.

• past perfect 《文法》過去完了（形）｛かこ かんりょう（けい）｝(definition from Eijiro on the Web)

My summary of how to use past perfect was this:

1. two past events
2. A happens before B
3. A is important for B

You should use past perfect to describe A.

For example:

• I was interested in ways to cook with Japanese mountain yam other than grinding it and putting it on soba. <- A  (Japanese mountain yam 山芋 )
• I experimented with stir-frying it. <- B, the reason for this was A
• Since I had been interested in ways to cook Japanese mountain yam other than grinding it and putting it on soba, I experimented with stir-frying it.

The sauce was made with miso, soy sauce, and sesame oil. It turned out delicious!

For more about past perfect tense, check these posts:

http://upgradeenglish.blogspot.com/2009/06/when-do-i-use-them.html
http://upgradeenglish.blogspot.com/2009/06/when-do-i-use-them-part-2.html
http://upgradeenglish.blogspot.com/2009/06/when-do-i-use-them-part-3.html
http://upgradeenglish.blogspot.com/2009/06/when-do-i-use-them-part-4.html

If you have any tips for cooking Japanese mountain yam, I'd like to hear them. Send me a comment or mail!