Answer:
can you comment the rest of the paragraph under this answer? i think you forgot it...
Answer:
1) has / playing / is preparing
2) while I was doing homework, my mother was arriving home
I know this may start controversy but it's not oppressed if they don't know they're oppressed. But if being abused then let them free yes, but on the terms of being oppressed then no.
The best thing you can do is be very detailed. For example if the drawing was about a tree, explain the branches and the leaves and the background. You can never have to many details! hope this helps! :)