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随意， ずいい， ずい
1. voluntary, optional, free, elective
自愿的、可选的、自由的、选择的
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結構， けっこう
1. splendid, nice, wonderful, delightful, lovely, excellent, fine
2. sufficient, satisfactory, enough, fine, all right, OK
3. not needing (any more of something), (already) having enough, fine (as in "I'm fine"), no, thank you
4. rather, quite, fairl...
足够、满意、够了、好(的)、没事、OK；不需要(任何东西)了、(已经)够了；很好(如 "我很好")；不，谢谢；相当；精彩的，美好的，奇妙的，愉快的，可爱的，出色的，精妙的；结构
する， 為る
1. to do, to carry out, to perform
2. to cause to become, to make (into), to turn (into)
3. to serve as, to act as, to work as
4. to wear (clothes, a facial expression, etc.)
5. to judge as being, to view as being, to think of as, to treat as, to use...
做，作，干，执行