It is a compound noun: two nouns joined together to make one idea.
Together they mean size label.
The hyphen helps readability here, especially because one part ends in -e and the next begins with e-. Afrikaans often forms compounds as a single unit, and a hyphen is sometimes used to make them easier to read.
Yes. Even though it is written with a hyphen, it functions as one compound noun.
The whole unit grootte-etiket is the subject of the sentence, not grootte and etiket separately.
So the structure is:
Yes, in this sentence it is very similar to English.
The pattern is:
So it follows a basic subject + verb + place phrase structure.
Also, Afrikaans main clauses usually place the finite verb in second position, and that is exactly what happens here.
Op means on.
In this sentence, it shows location: the size label is on the garment.
It is the normal preposition to use when something is physically on a surface or attached in an on position.