人体与外界的气体交换是通过什么方式实现的？（　　）

材料一：

材料二：

材料三：及秦孝公用商君，坏井田，开阡陌，急耕战之赏。虽非古道，犹以务本之故，倾邻国而雄诸侯。有国强者兼州城，而弱者丧社稷。

——《汉书·食货志》

材料四：当时，各家学派的代表人物聚众讲学，研讨学术，著书立说。它们提出各种政治主张和治国方略，希望用自己的学说解决社会问题。各学派在思想上、政治上的观点不同，学派之间展开激烈的辩论，相互抨击；同时又相互影响，取长补短，呈现思想文化的繁荣局面。

——人教版《中国历史·七年级上册》

底面半径R，高为h的圆柱与底面半径为r，高为h的圆柱的体积的比是9：25，则R：r等于（　　）

如图所示所描述的声音具有的共同点是（）

任务型阅读

    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.