摘要
春夏之交，气温变化频繁，是传染病多发的季节。你知道最有效的预防措施是什么吗？
We＇ve all been sick from time to time. Colds and the flu come along now and then, and they＇re no fun when they keep us from doing the things we want to do. That＇s wily people try so hard to stay healthy. Did you know that experts believe the most important thing you can do to avoid illness is wash your hands？ It＇s true!
