题目

任务型阅读Healthy Eating Healthy eating is important for us. What and how should we eat to be healthy? First, we must have enough food, never too much or too little. The food must be clean and we should cook it properly. Second, it's very important for us to keep a balanced diet. Different kinds of foods are necessary, such as rice, bread, meat, fish, eggs, milk, fruit and vegetables. Rice and bread give us energy. Meat, fish, eggs and milk help our bones grow. Fruit and vegetables make us healthy. Third, we should eat regularly. It's said that half of the students don't have a regular br在探究“力对物体运动的影响”的实验中，在水平桌面上分别铺上粗糙程度不同的毛巾、棉布、玻璃，让小车自斜面顶端从静止开始滑下，小车从同一高度滑下后，在不同物体表面上运动的距离如图所示．（1）实验时小车每次都从斜面顶端滚下，是为了让小车在这些物体表面开始运动的______相同．（2）由图可知，小车在玻璃上运动的距离最______，这说明小车受到的阻力越______，速度减小得越慢．（3）根据这个实验推理：若水平物体表面绝对光滑（即小车不受任何阻力作用），那么小车将______．（4）科学家经过大量类似实验，总结出了______定律，此定律的内容是一切______的物体，总保持______状态或______状态．这个定律______直接由实验来证明（选填“可以”“不可以”）．