（重写句子）Just 30 years ago, two out of three American families consisted of a father, a mother, and their children. Today, less than one family out of five fits that description. (compound sentence)
【正确答案】：Just 30 years ago, two out of three American families consisted of a father, a mother, and their children,(however) today ,less than one family out of five fits that description. // Just 30 years ago, two out of three American families consisted of a father, a mother, and their children, but today, less than one family out of five fits that description.