摘要：We might talk about the population of the planet Earth, the population of a city, and so on.
I'm thinking about a noun we use to talk about people on Earth.
我在思考一个用来描述地球上人类的词汇。
Can you guess what that noun is?
你能猜到那个名词是什么吗？
Humanity?
人性?
That's a good guess, but not the one I had in mind.
这是一个不错的猜测，但并非我心中所想的那一个。
What noun were you thinking of?
你想到了哪个名词？
Population.
人口。
It is a noun that means the number of people or animals living in an area.
它是一个名词，意指居住在某区域内的人口或动物数量。
We might talk about the population of the planet Earth, the population of a city, and so on.
我们可能会讨论地球的人口、某个城市的人口等等。
That makes sense.
这说得通。
When we talk about nouns, we often describe them as being either count nouns or non-count nouns.
当我们谈论名词时，通常将其描述为可数名词或不可数名词。
We can make count nouns plural by adding an s. We do not make non-count nouns plural.
我们可以通过加s使可数名词变为复数。不可数名词则不作复数处理。
English speakers commonly use population as a countable noun.
英语使用者通常将“population”作为可数名词使用。
Let's consider some examples to clarify these points.
让我们通过一些例子来阐明这些要点。
You might say, Researchers predict the world's population will increase next year.
你可以说，研究人员预测明年世界人口将会增长。
We use the singular form because we are talking about all the people who live in the world, one very large group.
我们使用单数形式， 因为我们讨论的是所有生活在世界上的居民，这是一个非常庞大的群体。
But we can also make population plural by adding an s. In this case, we might use other terms to show that we are talking about different groups.
但通过在“population” 后面加一个“s” ，我们也可以使其变为复数形式。 在这种情况下，我们可能会使用其他术语来表明我们正在讨论不同的群体。
For example, you might read a news report that says this, overweight and elderly populations are at greater risk of developing the illness.
例如， 你可能会读到一则新闻报道说，超重和老年群体患这种疾病的风险更高。
We used the plural form populations because we are talking about all of the members of two different groups, overweight people and elderly people.
我们使用复数形式“populations”，是因为我们在讨论两个不同群体——超重人群和老年人群体中的所有成员。
We can also use population to talk about groups of animals.
我们也可以用“population”来指代动物群体。
For example, bird and reptile populations are shrinking in North America.
例如，北美地区的鸟类和爬行动物种群数量正在减少。
And that's Everyday Grammar.
这就是每日语法。
来源：英语东
