Yes , if one who want to do MBA Executive from Wrocław University of Economics (Poland) then they must be fluent in English , as it is condition of admission requirement

Here I am telling admission requirement info

Candidates must be fluent in English
and must have Bachelor or Master's degree diploma;
documents conferring two-year working experience;
application letter, CV, medical certificate, 4 photographs (37x52 mm), copy of identity card.

Selection procedure involves interview with a candidate.

Enrolment: second decade of September

Wrocław University of Economics (Poland) offered Executive MBA Programme to provide managers and executives with an integrated vision of an organization in a competitive economy and to deliver knowledge and skills required to recognize and approach business decision problems, and to solve them in a changing environment.

The Master's Degree in Executive Business Administration is a two-year, part-time programme commencing in October.

It takes place on alternate Fridays and Saturdays.

The courses are divided into 4 broad categories:
Foundation,
Core,
Integration,
Orientation

Address
Uniwersytet Ekonomiczny
we Wrocławiu
ul. Komandorska 118-120
53-345 Wrocław

phone: +48 71 36 80 100
fax: +48 71 36 72 778
e-mail: kontakt@ue.wroc.pl
NIP: 896-000-69-97