A bitter white alkaloid, C8H10N4O2, often derived from tea or coffee and used in medicine chiefly as a mild stimulant and to treat certain kinds of headache.

咖啡因一种苦味的白色生物碱，C8H10N4O2，通常得自咖啡或茶，在药品中主要作为温和兴奋剂及治疗特定的头痛病。

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For the husband whom she had only seen once, she has spent the glorious youth on endless bitter waiting, and entrusted the girl's mild love to the blank dream night after night.

她为了只见过一面的丈夫，已经应掷三年，把锦绣青春都抛入无尽的苦等，把少女柔情都交付了夜夜空梦。

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But the post-war boom in lager - outstripping traditional tipples like bitter, mild and stout - offers some clues as to what made the drink so appealing to millions in the first place.

BBC: Has Britain fallen out of love with lager?

The bottled beers included Massey's 6d Special Mild Ale, Prize Stout, King's Ale, Golden Bitter Beer and Pale Ale.

BBC: If you live in Burney, you must have heard of Massey's.