Breakdown of Zanim zaczęliśmy badanie, rozmawialiśmy z wieloma grupami docelowymi.
rozmawiać
to talk
z
with
grupa
group
badanie
the examination
Questions & Answers about Zanim zaczęliśmy badanie, rozmawialiśmy z wieloma grupami docelowymi.
Why does the sentence use wieloma instead of wiele?
The preposition z (meaning "with") requires the Instrumental case. The indefinite numeral wiele must decline to match this case, becoming wieloma.
Does wieloma force the following noun into the Genitive case, like wiele usually does?
No, and this is a key rule! While Nominative wiele forces the Genitive (for example, wiele grup), in oblique cases like the Instrumental, Dative, and Locative, the numeral just acts like a normal adjective. It simply agrees with the noun's case, which is why both wieloma and grupami are in the Instrumental plural here.
Why is zanim used for "before" here instead of przed?
Zanim is a conjunction that introduces a full clause with its own conjugated verb (zaczęliśmy). You use przed (a preposition) when "before" is followed directly by a noun phrase, such as przed badaniem (before the study).
What does the ending of zaczęliśmy and rozmawialiśmy tell us about the speakers?