1. Reasons for changing verb tense The writer does this in order to: make a statement of general truth. Children in Asian countries spend most of their day in school or specialized academies. move from a general statement to specific examples. This is VERY common. There are many reasons for students to have jobs when they are university students. When I was a student, I worked in a pearl tea shop. show contrast between one time and another Twenty years ago, not many people knew how to use a computer. Today, most families have at least one computer in their home. Click below to practice time shifts.