Q:

Why is there multiple ways to say the same thing in Chinese such as 等, 等下, 等一下?

I'm confused about some words in Chinese, it seems like most of the time there are multiple ways to say the same word by adding some "basic particles"  around it.
Like: 等, 等下, 等一下
To an online translator, it seems to mean the same. Is there any difference? Why is it like this?
As a new learner this makes listening an reading very complicated, because I never know where to cut the words in my head.

A:

Why not?
English has the similar phenomenon. For example, the following phrases have the same meaning:
wait a bit
wait a mo
wait a moment
wait a second
wait a minute
wait a jiffy
wait a jiff
The following phrases have the same meaning:
等一下
稍等一下
稍等一等
稍等一會兒
等下 is not so common.
Usually, 等 means "to wait", not "to wait a second".
For example, 等人 means to wait for somebody.
It is different from "to wait a second".
"Wait" can mean "wait a second" in English.
等 is not the same as 等一下 in Chinese.

