做功和能置

做功在物理学中具有特定的含义．人推车时对车施加一个向前的推力，车在力的作用下前进一段距离，只有在这种情况下，物理学才认为是人对车做了功．人用的力越大，移动的距离越长，力的作用效果就越显著，人做的功就越多．

力和在力的方向上移动的距离，是做功的两个因素，缺一不可．你从地面上提起水桶时，水桶在力的作用下，向上移动了一段距离，你对水桶做了功．如果手提着水桶站着不动，虽然你用了力，但是水桶没有移动距离，你只是费了力气，没有对水桶做功，这叫“劳而无功”．这里，手提着水桶站着不动和将水桶挂在钓子上没什么两样．

做功是生产和生活中常见的现象．不仅人能做功，运动的物体也能做功．从斜面上滚下的钢球撞在木块上，能将木块推动一段距离；飞行的子弹能打穿物体，都是由于钢球和子弹克服阻力做了功的结果．

举高的物体也能做功．气锤从高处落下，能把木桩打入地下；高空落下的冰雹，由于做功而砸坏了地上的农作物．

形状变化的弹簧也能做功，钟表里被旋紧的发条慢慢地放松，带动指针嘀嘀哈哈走个不停．

一个物体能够做功，就是它具有能量．能量大的物体，做功的本领也大．风具有能量，人们就安装风车，利用风力做功．长江、黄河的水急流直下，蕴藏着很大的能量，人们筑起拦河坝，安上水轮机，让从高处落下的水推动水轮机旋转，带动发电机发电．

摘自《中国少年儿童百科全书》（浙江教育出版社）

    When high school started, Sally and I became best friends. We shared many interests and quickly became very close.When high school ended, we both cried because we would enter different 1 in autumn.

    Our first term of college life was 2, so we often sent long e-mails and encouraged each other. We missed each other so much! In the second term, I found some new friends and I felt very 3 with them. These were friends with whom I could be myself and pour out my feelings. I wanted to share my new friends with Sally.

    When Sally 4 visited me at my school, we were excited.

    She brought a toy bear to me 5a present and told me about her college life. 6, something unexpected happened when I introduced her to my new friends.Her eyes grew dark and I could see the sadness in them.My new friends tried to share their friendship, but Sally seemed unwilling to accept it.I didn't understand 7the people I loved most couldn't love each other.

    Sally left. I knew she was not happy. I thought long about what had happened. I asked her many questions but she didn't answer me. I 8 that she was jealous(嫉妒). She saw me with my new friends and was afraid that we no longer shared the same experiences. She saw that I could still enjoy myself  9 her and wished she could be a part of it.

    I wrote Sally a letter to 10 she's always my best friend. I told her everyone had friends from home and friends from school, and all the friends were indeed life's greatest 11.Sally wrote me back soon. She was in agreement and felt sorry about 12 she had done.

    I think Sally and I both 13 an important lesson from it. Nothing can influence our 14  and change the experiences we've shared.We are now walking on two different paths of life. While new friends are special and exciting, old friends are 15 there, waiting to share their heart, no matter how far away they are from each other.

下列句子中，没有运用比喻修辞手法的一项是（    ）

“完善旅游设施和服务，大力发展乡村、休闲、全城旅游。”这是“全城旅游”首次写入2017年政府工作报告。近年来，旅游业正在从景点旅游向全城旅游转变，旅游将从传统旅游发展到“旅行”，进而发展到“旅居”，全城旅游契合了当下旅游业的发展趋势。大力发展全城旅游（  ）