WRITING HOMEWORK : What do you usually do on the weekend?
Once, I wake up lately on Saturday and spend time with my friends or family. = On the weekend, I wake up late on Saturday and spend time with my friends or family.

And I always have lunch or dinner with my family on Sunday. This is because all my family members busily work on weekdays,= This is because all my family members are busy with work on weekdays, so we can’t eat or spend time together. 

So, we are it is indispensable to spend time together on Sundays. In Yesterday, my family had a delicious lunch and then, visited a department store in Gwangju for buying the father’s present. = to buy a present for my father.