The contest Beaver of Informatics is the first contact with informatics and informatics topics like algorithms, programming, or modeling for many pupils. It's important for tasks in this contest to be correct and representative. Students of Faculty of Education at University of South Bohemia, pre-service teachers, are tasked with preparing tasks for this contest. They are given these tasks in English and are supposed to translate them and prepare them for the contest. The aim of this research is to analyze these tasks and to find what errors pre-service teachers do. We found out that the biggest problems are putting grammatically correct sentence together. The sentences were left with English word order. Because of that, tasks were hard to read and sometimes didn't make sense.