141．There is no doubt that our educational system leaves something to be desired.

　　毫无疑问，我们的教育制度令人不满意。

　　142．An advantage of using the solar energy is that it won‘t create any pollution.

　　使用太阳能的优点是它不会产生任何污染。

　　143． The reason why we have to grow trees is that they can supply fresh air for us.

　　我们必须种树的原因是它们能供应我们新鲜的空气。

　　144．So precious is time that we can‘t afford to waste it.

　　时间是如此珍贵，我们不能浪费它。
 

　　145．Rich as our country is, the qualities of our living are by no means satisfactory.

　　虽然我们的国家很富有，但是我们的生活质量却令人很不满意。