Questions & Answers about Potřebuji pár kopií.
Potřebuji means I need.
It is the 1st person singular present tense form of the verb potřebovat, which means to need. So:
- potřebovat = to need
- potřebuji = I need
In this sentence, it works just like English I need.
Czech often leaves out subject pronouns when they are not needed.
The ending in potřebuji already tells you the subject is I, so já is unnecessary here.
So both of these are possible:
- Potřebuji pár kopií. = I need a few copies.
- Já potřebuji pár kopií. = I need a few copies.
The version with já sounds more emphatic, as if you are stressing I.