Because Afrikaans verbs usually do not change form for person or number in the present tense.
So you get:
Unlike English, there is usually no extra ending like uses versus use.
'n is the Afrikaans indefinite article, the equivalent of English a or an.
A few important points:
For example:
So in this sentence, 'n introduces the noun phrase 'n klomp glip.
Because Afrikaans can put 'n klomp directly before a noun:
So 'n klomp glip follows a normal pattern in that respect.
You often see van when the phrase is followed by a more definite group or a pronoun, for example:
So the absence of van here is not the strange part.
Yes, in this sentence glip has to be functioning like a noun, because it comes after 'n klomp as part of the object phrase.
That is exactly why this sentence may feel odd to a learner: glip is more commonly recognized as a verb meaning to slip.
So the grammar frame is understandable, but the word choice is unusual unless there is some special context where glip is being used as a noun or technical term.
Often, yes: if the following word is a normal countable noun, Afrikaans usually uses the normal plural form after 'n klomp.
For example:
That is one reason 'n klomp glip sounds a bit unusual. If glip is meant as a regular countable noun, many learners would expect some clearer plural form or a different wording. If it is being treated as a mass noun or jargon term, the singular might make more sense.
So this is less about a general grammar rule being broken, and more about the phrase sounding non-standard or context-dependent.
A native speaker would probably find the structure natural, but the combination 'n klomp glip sounds unusual without context.
In other words:
So if this comes from a textbook, exercise, or machine-generated example, it may be grammatically shaped like Afrikaans but not be a very idiomatic everyday sentence unless there is a specific specialized meaning intended.