Answer:
1. In the past, people used to write a letter to each other. Now they send e-mails to each other.
2. Do people in the past used to write with a ball point pen? Now we use it a lot.
3. My mother used to not wash my clothes when I was a student.
4. Bold used to be thin, now he is fat.
1. In the past, children used to do sums with an abacus. Now they use a calculator.
2. Before, children used to not ride a school bus to go to school. Now they go by bus.
3. Do they used to live in a small house?
4. Zaya used to not have a lot of books before.
Step-by-step explanation:
Just insert "used do" and "do" verbs.