人（“person”/“people”）
Unnatural English：
“These are five persons in each group.”
Natural English:
“These are five people in each group.”
Chinese:
每组有五个人。
上面的第一个句子应该说是对的。可是“persons”这个词听起来不是很自然。
通常情况下，如果我们想用“person”的复数形式，应当用“people”而不是“persons”。
“persons”是很正式的词，比如说，它经常用于官方语言中。
Explanation：
The first sentence above is not wrong，but“persons”sounds a little unnatural. Generally if we want to use the plural of “person”, we say “people”,
not “persons”. “Persons” is very formal and used, for example, in official language.
Example:
“These are thirty-four people in the freshman English class and twenty-eight people in the sophomore
English class.”
“My family has four people-my mother, father, and sister.”
“A lot of people went to the dance at the student activity center on Friday night.”
“Millions of people were killed in World War ll.”
(formal use of “persons”) “Any person or persons littering on public property will
be fined one thousand dollars.”
