студенты жаловались, что, они тщате

студенты жаловались, что, они тщательно готовились к экзамену в течение трех дней, у них не было ясного представления о многих вопросах.

Результаты (английский) 1:

students have complained that they are carefully prepared for the exam within three days, they did not have a clear understanding of many issues.

Результаты (английский) 2:

Students complained that they are thoroughly prepared for the exam within three days, they did not have a clear idea about many issues.

Результаты (английский) 3:

Students complained that they prepared for the exam in the course of three days, they had not had a clear presentation of many of the issues.