12. ____ the police know the killer's identity, they are getting close to catching him.
To their surprise, they found the lecture given by the famous professor easy ______.
If you are not familiar ____ the topic, you may write something that is familiar ____ you.
We would rather die than ______ difficulty.
Go about your business your own way. Don’t _____what others think or say.
___________ to enter an ideal university, he worked harder than ever before.