题目

 语法填空 阅读下面的材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。 World Sleep Day, organized by the World Sleep Day Committee of the World Association of Sleep Medicine since 2008, is   1  ( hold )on March 21 every year. The aim of World Sleep Day is to celebrate the benefits of good and healthy sleep. Sleep quality plays a key role in   2  (people) health. Researchers say that there 3(be) a lot of advantages if we always get enough sleep. We can be smarter, thinner,   4  (health) and more cheerful. Also we’re to have bet18．如图，半圆S1的面积是14.13平方厘米，圆S2面积是6.28平方厘米．长方形（阴影）的面积是多少平方厘米？