Generalities
There are two kinds of generalities: precise and vague.

Precise Generalities
They involve a more black and white approach in the argument.

An example of this "Less than 5% of the students in a chemistry class actually understand the material. Mary is in that chemistry class. So she does not understand the material. On the other hand, vague generalities use generic terms, such as most, many, and almost all.

Vague Generalities
Words that are too vague tend to make it difficult to figure out if the argument is valid. Words such as a few or a lot are too vague. But almost all and very few are two vague generalities that we can use in strong arguments.

For example, “Almost all students study” versus “A lot of students study.” The one with almost all sounds more concrete since it’s stating that not all students study. But as for the claim using a lot, it’s vague leaving you wondering how many students study? How many is a lot?