困難， こんなん
1. difficulty, hardship, trouble, distress
2. infeasibility, inability (to carry out)
困难；不可行性，无能为力（执行）
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苦労， 苦勞， くろう
1. trouble, hardship, difficulty, labour, labor, toil, pains
2. anxiety, worry, concern, cares
麻烦，艰辛，困难，劳动，劳作，辛劳，痛苦；焦虑，忧虑，关切，烦恼
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@ 挑む， いどむ
1. to challenge to (a fight, game, etc.), to throw down the gauntlet, to contend for
2. to tackle (e.g. a problem), to attempt, to go after (a prize, record, etc.)
3. to pressure (someone) for sex, to make advances to
向（战斗、比赛等）发起挑战，掷下挑战书，争夺；解决（如问题），尝试，争取（奖项、纪录等）