题干

化学在生产和生活中有重要的应用.下列说法正确的是(   )

A:新型材料聚酯纤维、光导纤维都属于有机高分子

B:14C可用于文物年代的鉴定,14C与12C互为同素异形体

C:凡含有添加剂的食物对人体健康均有害,不宜食用

D:“开发利用新能源”、“汽车尾气催化净化”都能提高空气质量

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D

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    Getting your children to study can be a little like getting them to eat their vegetables. ____ Make a study time and have it at the same time every day. This will help your kids to learn to schedule their day and will give them a sense of control over how they spend their time.

    Allow them to study in blocks of time,such as for half an hour with a five-minute break in the middle. ____ Ideal(理想的) study times are after dinner or right after school before dinner.

    Never allow your children to study in front of the television,as that will encourage passive activity. ____ You'll also need to help your kids find the right place to study. After you've set up a good study time for little learners,set up a good place where they can get those creative juices flowing. ____ Make sure there is a table or a desk and a comfortable chair.

    ____ This includes helping them out with their homework sometimes and being there for them with the answers to any questions. The input you give your children during study periods will help form a bond and help make studying enjoyable.

A.Pick a place where your children can study properly.B.Hold them to the schedule they create for themselves.

C.Finally,spend time with your kids when they're studying.

D.Keep the atmosphere light and offer lots of encouragement,too.

E.Instead,use TV as a treat or a reward when the homework is completed.

F.Try to stop this bad habit by offering some sort of reward.

G.One of the best ways to form good study habits for your kids is to design a schedule that they keep to.