--- He’s never late for school, _____ he?---_______________, but once he asked for a sick leave（病假）.

—What do you think of tomorrow’s football match?—_____ difficult for us_____ the match.

——Mary stays alone in the classroom and looks sad.——________ to her?

---      do you surf the Internet?  --- Once a week.

---Will people live to be 300 years old?   ---__________.