When reading the book, it gives a lot of students may or may not be tired because of the need to read a book all night, and when I want to take the exam later in the day will cause drowsiness and exam students.
When I was reading the book, students may be tired or did not sleep all night because of the need to read and to take the exam at a later date to make students drowsy and exams are not full.
When you read a lot, it makes the students tired and could not sleep because of the need to read the whole night and when to exam the next day will make students tired and do test not fully.