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number one; first; first place
best; most
game; round; bout
as a test; as an experiment; by way of experiment; by way of trial; tentatively
song (e.g. in noh); piece
これが一番おいしい。
This is the most delicious.
この中で一番高いのはどれ?
Which is the most expensive?
一番大切なことは健康だと思う。
I think the most important thing is health.