独一无二的英文：
alone
one of a kind
in a class by oneself

参考例句：

Starch is unique among carbohydrates because it occurs naturally as discrete particles (granules).
淀粉在碳水化合物中是独一无二的,因为它作为个别微粒自然产生。

The beauty of Dunhuang is unique in the world.
敦煌的美在世界上是独一无二的。

an event singular in history
历史上独一无二的事件

Each person's fingerprints are peculiar to himself.
每个人的指纹都是独一无二的。

There's one man who's considered irreplaceable.
有一个人被认为独一无二。

Each person's signature is unique.
每个人的签名都是独一无二的。

A unique event, without parallel in history.
历史上独一无二的事件

With regard to hardness, the diamond is in a class by itself.
讲硬度，金刚钻是独一无二的。

Exclusively fine champagne Cognac.
独一无二的醇美香槟白兰地。

His skill in chess is unmatched in the school.
他的棋艺在全校是独一无二的。

alone是什么意思：
adj. 单独的，独自的；只有，仅
adv. 单独地，独自地

He has a yen to be alone in a boat.
他渴望独自待在一条船上。

But many are unwilling to act alone.
但是许多人却不愿单独行事。

He is used to drinking alone.
他已经习惯了一个人喝酒。

kind是什么意思：
n. 种类；性质
adj. 和蔼的；宽容的；友好的

Kindness always begets kindness
善有善根

Certain kinds of wine go with certain kinds of food.
某些酒与某些饭食相配。

The kindness of caring for—saying of the sons for their parents’ kindness
顾复之恩

class是什么意思：
n. 班级；阶级；种类
v. 分类；把…分等级
adj. 很好的

It is a step class.
这是踏板操训练班。

The class dismissed.
下课了。

The class teacher sectioned the class for dialogues.
老师把班级分组进行对话练习。