题干

下列说法中错误的是(   )

①化学性质相似的有机物是同系物

②分子组成相差一个或几个CH2的有机物是同系物

③若烃中碳、氢元素的质量分数相同,它们必是同系物

④具有同一通式的物质属于同系物.

A:只有①②③

B:只有①②④

C:只有①③④

D:①②③④

上一题 下一题 0.0难度 选择题 更新时间:2019-10-27 10:28:45

答案(点此获取答案解析)

D

同类题5

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Forgiveness

    To forgive is a virtue, but no one has ever said it is easy. When someone has deeply hurt you, it can be extremely difficult to let go of your hate. However, forgiveness is possible, and it can be surprisingly beneficial to your physical and mental health. People who forgive show less sadness, anger and stress and more hopefulness, according to a recent research.

    ____ Try the following steps:

    Calm yourself. ____ You can take a couple of breaths and think of something that gives you pleasure: a beautiful scene in nature, or someone you love.

    Don't wait for an apology. Many times the person who hurt you does not intend to apologize. They may have wanted to hurt you or they just don't see things the same way. ____ Keep in mind that forgiveness does not necessarily mean becoming friends again with the person who upset you.

    Take the control away from your offender(冒犯者). Rethinking about your hurt gives power to the person who causes you pain. Instead of focusing on your wounded feelings, learn to look for the love, beauty and kindness around you.

    ____ If you understand your offender, you may realize that he or she was acting out of unawareness, fear, and even love. You may want to write a letter to yourself from your offender's point of view.

    Don't forget to forgive yourself. ____ But it can rob you of your self-confidence if you don't do it.

A. Why should you forgive?

B. How should you start to forgive?

C. Recognize the benefits of forgiveness.

D. Try to see things from your offender's angle.

E. For some people, forgiving themselves is the biggest challenge.

F. To make your anger die away, try a simple stress-management technique.

G. If you wait for people to apologize, you could be waiting an awfully long time.