sole

only, single, sole, unique, alone

这些形容词均可表示“唯一的”之意。
only: 普通用词，常可与sole换用，但侧重仅限于指定的人或物，而不需要更多。
single: 语气较强，强调仅此一个，再无第二个。
sole: 语气强于only，指仅有一个或一群，只考虑这一个或这一群。
unique: 非正式用词，侧重在一类中唯一无可匹敌、无与伦比的特征。
alone: 着重专指某人或某物，而不是别的。

名词 sole:

1. the underside of footwear or a golf club
2. lean flesh of any of several flatfish
   同义词：fillet of sole
3. the underside of the foot
4. right-eyed flatfish; many are valued as food; most common in warm seas especially European

动词 sole:

1. put a new sole on
   同义词：resole

形容词 sole:

1. not divided or shared with others
   同义词：exclusive
2. being the only one; single and isolated from others
   同义词：lone, lonesome, only, solitary

1. The book has no artistic merit and its sole aim is to titillate (the reader).
   那书毫无艺术价值，只是撩拨(读者)情欲。
2. The sole redeeming feature of this job is the salary.
   这份工作唯其薪水尚可弥补一切之不足。
3. Farming is his sole livelihood.
   他唯一的谋生之道就是务农。
4. Drunkenness is his sole vice.
   酗酒是他唯一的恶习。
5. His sole motive is to make more money.
   他唯一的动机就是多赚钱。
6. The soles of my shoes are broken.
   我的鞋底都断了。
7. I'm having my shoes soled and heeled.
   我要叫人给鞋子换鞋底和鞋跟。
8. The sole survivor of the crash was a little boy.
   这次撞车事故的唯一幸存者是一个小男孩。