_____ is a good form of exercise for both young and old.
8.The silence of the library is sometimes broken by a sudden cough or the sound of pages__________.
7.John’s ability to learn from observations and experience_______greatly to his success in public life.
6.--- Is there any possible way to help them get rid of such a bad habit? --- To tell the truth, it’s very hard. But we teachers________on this problem.
5.--- Thank you every so much for your timely help. --- .
4.Good news came that Nancy decided to donate blood to DanHeins, and the results of the medical tests came in: She was a___________.