At times, worrying is a normal __________ to a difficult event or situation—a loved one being __________ in an accident, for example.
________her home, Mary helps her mother with some housework.
They often _______their friends at weekends and they always have a good time.
Do you think everything _______was true?
It was Tom and his friends that________for the serious accidents.
He was reading a very interesting story, completely_______himself in the story.