题干

烧开水要从锅的底部加热,冷冻温水要把冰块放在上面,为什么?试用所学知识加以解释.
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答:烧开水时底部水受热膨胀上升,密度减小而上升,形成对流,使加热时间缩短;冷冻从上面开始,能使上面的水受冷收缩,密度增大而下降.也是为了形成对流,使冷冻时间缩短.

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    Do you still remember your favorite poem from high school or some other important periods in your life?Why is it that decades later it still stands out in your mind?Probably the main reason is that some aspects of that poem resonates(引起共鸣)with you.In the same way,you too as a school leader can touch the hearts of your staff and students.

    Poetry allows us to experience strong spiritual connections to things around us and to the past.Thus,it can inspire whatever and whomever it touches.The power that poetry has displayed over time and across cultures actually satisfies this common need of the human heart and soul.

    As one of the oldest art forms,poetry has successfully connected various strands of humanity(人性)from one generation to another.Referring to poetry,Hillyer makes a simple yet meaningful statement,“With this key mankind unlocked his heart.”

    School leaders can find and make use of the value of poetry for themselves,their students and their staff members.Beyond the simple use of poetry,techniques of poetry such as metaphors,repetitions and imagery can be used to take advantage of the power of language to transform communication,create meaning and a culture of care and attention.

    Since schools are mainly about people and relationship,school leaders,like poets,are required to inspire and encourage the human heart.The use of poetry—or even of some techniques of poetry—in school leadership not only helps to improve communication,but also serves to meet the human need for inspiration.