keen adj.
VERBS appear, be, feel, look, seem, sound | remain
ADV. awfully, desperately, especially, extremely, frightfully, mad (informal), more than, particularly, really, terribly, very He's mad keen on football. She's a very keen gardener. | not at all, not overly, not too The banks were not at all keen to lend to somebody who actually seemed to need money. | fairly, pretty, quite, rather | always She was always keen to hear the local gossip. | obviously | naturally, understandably She was naturally keen to make a good impression.
PREP. for They were desperately keen for information. | on Sally's quite keen on the idea.
PHRASES as keen as mustard (= very keen)
You can also check other dicts: keen (English, 中文解释 ), wordnet sense, Collins Definition