Experts say walking is one of the best ways for a person to _____ healthy.
When did you------ English? When I was in college.
We’ll look into the case as soon as we can. Just be ________, please.
How the big forest fire has ________ remains to be a mystery.
Only ______ a human being.
---Why didn’t you tell me the truth about his illness? ---___________, I knew nothing about it at that time.