all

attr ... head ... date=2003/05

attr ... head ... date=2005

attr ... head ... time=02

attr ... from=from1@iware.co.jp

attr ... to=to2@iware.co.jp

attr ... importance=2

attr ... attach=ppt

1*2
attr ... head ... date=2004
attr ... importance=1

1+2
attr ... head ... date=2004/01
attr ... head ... date=2004/02

