"差不多" (chàbùduō) can be used as an adjective or an adverb to express that aspects of one or more things are close to each other or the difference between them is small.

Structure as an adjective:
As an adjective, "差不多" can be placed directly after the subject of the sentence and, when coupled with a "的", can modify nouns.

Examples:

Zhè liǎnɡ kuǎn diànnǎo chàbùduō, nǐ yào nǎ ɡè?
这 两 款 电脑 差不多，你 要 哪 个？
These two computers are almost the same, which one do you want?

Wǒmen de zhōnɡwén shuǐpínɡ chàbùduō.
我们 的 中文 水平 差不多。
Our levels of Chinese are more or less the same.

Structure with an adverb:
When using "差不多" as an adverb, place it before the adjective or verb.

Examples:

Wǒmen chàbùduō ɡāo.
我们 差不多 高。
We are more or less the same height.

Wǒ zài nàlǐ ɡōnɡzuò le chàbùduō èr shí nián.
我 在 那里 工作 了 差不多 二 十 年。
I worked there for almost twenty years.