【单选题】听力原文: Recent research has claimed that an excess of positive ions in the air can have an ill-effect on people's physical or psychological health. What are positive ions? Well, the air is full of ions,...
【单选题】世界卫生组织推荐的人类食用油脂肪酸标准为: 饱和脂肪酸∶单不饱和脂肪酸∶多不饱和脂肪酸=1∶1∶1(物质的量之比),下列选项中按饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸顺序排列的是( ) ①C 17 H 35 COOH;②C 17 H 33 COOH;③C 15 H 31 COOH;④C 17 H 31 COOH;⑤C 17 H 29 COOH
【简答题】A wave of recent research has pointed to the risks of over praising a child. And it seems that how to draw a line between too little praise and too much has become a high-pressure _ _ act for parents....