20世纪40年代,Paul Muller因发现DDT的杀虫剂作用而获得诺贝尔奖;60年代因发现DDT的累积性和持久性对人类健康和生态环境潜在的巨大危害,遭到世界各国的禁用;2002年世界卫生组织宣布,重新启用DDT用于控制蚊子的繁殖以及预防疟疾,登革热,黄热病等在世界范围的卷土重来。这告诉我们 ①客观事物是复杂的、变化着的 ②事物的发展的趋势是前进性的③事物的发展取决于认识的深化 ④要用辩证否定的观点分析事物
The girl ________to be a good dancer if she is well trained in an art school.
The performance supposed to be popular ________to be a great disappointment after it was over.
—Did you go to see the play last night? —Unluckily, I couldn't ________it. But I am going to see it soon.
—Did anyone support you at the meeting? —Moore was the only person who ________my opinion.
Having a trip abroad is certainly good for the old couple, but it remains ________whether they will enjoy it.