AIDS is said________the biggest challenge to both men and women in that area over the past few years.
—You still have one hour to wait, so relax. —How can I relax when I'm so __________ about the interview !
The power failure made __________ difficult for us to complete the task on time.
I promise that everything __________ clear about it next week.
They lived a hard life and were often made __________ for over ten hours a day.
—How do you keep __________? —I keep __________ every day.