There is no simple or single factor that determines if a given site will be a savanna, but some factors seem to play important roles in their formation.

没有什么简单或单一的因素能决定一个给定的地点是否会成为热带草原，但部分因素似乎在热带草原的形成中扮演着重要的角色。

youdao

You have a choice of coed or single-sex swimming exercise classes.

你可以选参加男女混合或是非混合的游泳练习课。

《柯林斯英汉双解大词典》

At the end of her life, almost blind, she saw what she could: the "mighty big clouds" above Texas, or single blooms through a magnifying glass.

在她生命的尽头，她几乎失明，能看见的只有：得克萨斯州上空“硕大的云朵”，或通过放大镜看一朵花。

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They agreed to a single primary for all candidates from any party, or no party, in congressional,statewide and legislative races.

VOA: special.2010.06.12

So we haven't gotten to molecules yet, we're just talking about single atoms or single ions, but what's nice is just talking about this very straightforward principle of atomic radius.

我们还没有开始讲分子，我们仍然只是在讨论单个原子或离子，但它的好处在于可以讨论,这个关于原子半径的非常简单直接的原理。

麻省理工公开课 - 化学原理课程节选

And then hash character takes in any string or character, single character, gives me back a number. Notice what I do.

然后哈希接受任何字符串或字母，单个字符,返回给我一个数字，注意我要做什么。

麻省理工公开课 - 计算机科学及编程导论课程节选

Temperatures plummeted to the low teens or single digits in spots and people got really cold.

FORBES: My Prediction Was Wrong: Why We Didn't Get To $8 Natural Gas

Easter Island, Chile, is equally impressive to families with children, couples or single travelers.

FORBES: 10 Trips That Will Change Your Life

There cannot be a single person or a single institution or a government blamed.

BBC: Foot-and-mouth: Do you want a public inquiry?