Studies show that office workers are more ______to suffer from backache because they always sit before computer screens for long hours.
The math problem is so hard. I really don’t know _____.
She told us _____ story that we all forget about the time.
At that time, Tom was _____one-year-old baby.
Mr. More has more money than Mr. Little. But he doesn’t enjoy_____.
Great changes ___________in my hometown in the past 30 years.