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very; greatly; terribly; awfully
immense; enormous; great
serious; grave; dreadful; terrible
difficult; hard; challenging
たいへん美味しかった。
It was very delicious.
今日はたいへん寒くなるらしい。
It seems it will be very cold today.
先生にたいへんお世話になりました。
The teacher helped me a great deal.