unhappy、unfortunate、unlucky与disastrous这些形容词均有“不幸的”之意。
unhappy : 多用于表示心理状态，指由于不满意或遇到一般性倒霉事而感到不愉快。
- That's enough to make anyone unhappy.
所有人都会因此而忧伤。
unfortunate : 语气较强，多指因命运不佳，意外不幸或事业失败、生活处于困境等而感到不幸。
- She has inherited her father's large nose, which is very unfortunate.
她遗传了父亲的大鼻子，真是太不幸了。
unlucky : 指因缺少或一时无机遇，虽作了努力，但事不从心，感到失意。
- The couple were unlucky enough to be in the hotel when the terrorist group struck.
当恐怖团伙袭击这家宾馆时，很不幸这对夫妇正住在里面。
disastrous : 着重不可避免和后果严重。
- This decision will have a disastrous impact on foreign policy.
这个决定将对外交政策产生极为不利的影响。
